The final task prior to hemming the trousers is to attach the buttons. Begin by laying out the button placement. I transferred their position on the fly first, setting their distance from the fly seam equal to the distance of the buttonholes from the fly edge.

Next mark the position of the front suspender buttons on the waistband. I like to make the first one about 2 1/2″ from the side seam, and the second one another 2 1/2″ from the first. Both are placed about 1/2″ below the top of the waistband.

Finally, mark the back button position about 1″ from the end of the waistband and 1/2″ from the top edge.

Attaching the Buttons

To attach the buttons, begin by passing a knotted thread from the wrong side through all layers.

Pass the thread through opposite holes of the button.

Make two complete passes through the button, passing the needle and thread back to the underside, and keeping the stitches rather loose. After this second pass, you can adjust the final height of the button by holding the button at the desired height and gently drawing the threads to the correct height. The height should be just slightly thicker than the suspenders or the fabric that will be attached to it.

The two stitches give just enough tension that the button will not move out of position, yet at the same time not be difficult to move if you want to.

After four or so stitches, begin making stitches in the other direction, forming a cross. The number of stitches depends on the strength of your thread and the thickness of the fabric. I’ve gone as many as six stitches in each direction.

Be sure to regulate the height with each stitch – at this point it’s impossible to change the height so any individual loose or tight stitch will affect the other stitches.

Pass the thread back to the right side one last time, and wrap the thread around the previous stitches 6 – 8 times, depending on the height, and pull firmly, forming the shank. This provides a durable finish to the buttons, helping to prevent them from falling off.

Finally, pass the thread through the shank three times in alternating directions to secure it, and trim the excess thread.

A waistband was usually found in the back of trousers to help adjust the fit as well as take stress off of the top of the seat seam.

Begin by cutting out two each of fashion fabric, lining, and optionally, linen. The linen is a good way to reinforce the belt, but is completely optional, especially if you’re using heavier fabric.

Place the lining and wool pieces right sides together, and then place that assembly on top of the linen, if using it.

Stitch around the belt using a 1/4″ seam allowance, and leaving a gap in the stitching about 1 1/2″ to 2″ for turning right side out.

A smaller gap means less hand sewing later on, but also makes turning right side out a bit more difficult.

When you get to the corners at each end, instead of making a sharp 90 degree turn, make a stitch across the corner as shown, giving room for the fabric when you turn it.

Trim the corners down to about 1/8″ to help in the turning process.

Turn the belts right side out.

I used a dull pencil to help get the points turned crisply.

Press the belt carefully after turning.

Close up the belt with a small felling stitch.

Repeat for the other belt.

Next, choose one belt to hold the buckle, and fold it around the buckle, basting it by hand with a couple of stitches. Mine’s turned under about 3/4″. Sorry I somehow forgot to take photos here but I believe it’s all in the video.

Then, getting your presser foot as close as you can, sew along the edge of the buckle, then out and around forming somewhat of a box shape to keep everything nice and secure. It’s helpful to use a piping foot here on your sewing machine, but I simply allowed the regular foot to sit on top of the buckle and turning the machine by hand so as not to accidentally sew into the metal buckle.

Next, buckle the belt securely, which makes laying the belt out on the trousers a little easier.

Lay the buckle on the trousers, the buckle centered over the split point in the seat seam.

Measure the distance from the top of the belt to the waistband on each side to ensure they’re at the same height.

Baste across the belt from end to end, being sure it’s in the correct position after basting. It’s a good idea to double check your measurements, mine were off slightly so I ended up adjusting.

When you’re happy with the positioning, draw a vertical line across the buckle where you would like the top stitching to be.

Top stitch around the belt edge and across the belt at the mark through all layers of the seat.

Here’s my completed belt after top stitching.

It’s a good idea to reinforce various stress points with bar tacks, especially if you have not done so on machine. I’ll be adding a bar tack to each side of my watch pocket, the back of the trousers at the split in the seat seam, and the bottom of the fly. You could also add one at the top and bottom of each side seam pocket.

Begin by knotting the silk buttonhole twist and passing it through from the wrong side through all layers.

Make a stitch about 1/4″ in length across the seam or area you are reinforcing, catching as many layers as you can. You could make it a prick stitch, passing the needle all the way through, in order to get through all of the layers.

I usually make a total of four stitches in place, but you could do more depending upon the thickness of your thread.

Now pass the needle crosswise between the stitches you just formed, catching some of the fabric underneath as well.

The number of these small stitches depends upon the length of your bar tack but eight seemed to work best in my case.

Pass the needle and thread to the wrong side and finish with a few back stitches in place. Here’s the completed bar tack, continue tacking the rest of the desired areas.

The bottom of the fly is tacked to give more strength to this very stressed area.

Here’s the watch pocket after tacking. You could do the side seam and open-top pockets in the same manner.

And finally but most importantly, tack the top of the seat seam just where the split begins.

At last we can begin to sew the inseams and seat seam, turning our work into something that actually looks like a pair of trousers. To begin work on the inseam, lay one leg in front of you, folded right sides together.

Pin the inseam together at the fork. There is a bit of excess fabric built into the pattern that needs to be fulled in here when basting.

Aligning the trousers at the hem, begin basting the inseam from the bottom towards the fork. Baste evenly until you get a couple of inches above the knees, or roughly two-thirds of the way to the fork.

You’ll notice now there is some extra fullness in the seat of the trousers that needs to be fulled in to the inseam. Continue basting towards the fork, carefully distributing the fullness as you go.

Here’s my inseam after basting. You can see the fullness that has been worked in. For that last little fold on the right side, I’d say that was a little too much fullness and to go back and baste that area again.

Place the trousers on the ironing board, back side up, and gently full or shrink out the extra fullness that was basted in using a bit of steam as necessary. As your pressing the iron in small circular or back and forth motions, the fabric will gently shrink away. Try to keep the iron within an inch or so from the edge to avoid shrinking more of the trousers than we want.

Sew the inseam by machine or using a back stitch (or back and fore stitch), keeping a 1/4″ seam allowance.

Remove the basting stitches and press open the seam from both sides, using a pressing roll as necessary.

The Seat Seam

Moving on to the seat seam, this step can be a little confusing – I almost always get it mixed up. Turn the left side of the trousers, with the buttonholes, right side out. Turn the right side of the trousers inside out.

Then insert the left leg into the right leg, so that they’re right sides together. Roughly align the seat seam at the fork / side seam as best you can. This makes sewing the seat seam a little easier than if we had done things the opposite way.

Line up the side seams at the fork for each half as closely as possible.

Now baste the seat seam together from the side seam to the bottom of the fly, or just beyond it for more stability. Be sure that the cut you made during the fly construction lines up with the bottom of the button catch. Smaller basting stitches are best to keep things from moving around.

The completed basting here stabilizes the seat seam so we can move on to basting the rest of the seam now.

Aligning the backs of the waistband first, baste from just below the waistband to the fork at the side seams.

Make a mark on the inner side of the seat seam (I’m showing the mark on the outer side in the photo) about 2″ or 3″ below the waistband depending on your size and preferences, to denote the opening of the back.

This will indicate the upper end of the stitching.

Sew the seat seam starting at the bottom of the fly through to the mark you just made. Sewing the area near the fly can be tricky due to all of the layers. Try to carefully manipulate and fold the fly out of the way to get as close as you can with your stitching to the bottom of the fly.

Then repeat the process and sew a second line of stitching almost directly on top of the first line. This will greatly strengthen the seat seam and help keep the seam from splitting open.

You can see how close I got to the fly seam here, it’s maybe 3/16″ off. If you can get closer that’s great but not strictly necessary as the fly will be secured further in a bit.

Here’s the same area from the other side. I realized I caught part of the seam allowance in the seam, but chose to leave it, as it’ll be pressed over in that direction anyway.

Here’s a section of the seat seam towards the back, you can just make out the two rows of stitching.

Finally, press the seat seam open from the wrong side, followed by the right side as usual. It’s somewhat difficult to get to all of the angles, so I use a tailor’s ham placed inside the seam and manipulate the fabric as necessary.

Topstitching the Fly

One last bit to do that I consider as part of the seat seam is to secure and top stitch the fly to the button catch, further strengthening the area and preventing the fork from tearing open. Lay the trousers right sides up, the fly facing you.

It’s hard to photograph, but align the fly carefully along the bottom, and baste securely through all layers. In the photo, I’ve got my left hand grasping the fly from underneath the fabric.

The fly after basting the lower area.

Now draw a small line across the fly, at least 1″ below the lowest buttonhole, to indicate the stitch line. This should be perpendicular to the edge of the fly, not necessarily parallel to the floor.

Sew across the width of the fly through all layers, being careful to not catch any other parts of the trouser underneath, such as the back side or the pockets. That’s happened to me all too often and it’s a pain to undo!

As there are many layers in this area, be sure to use a sturdy enough needle, at least a size 100. Even with that you may break a needle here depending on the fabric you’re using. Luckily this was a fairly light weight fabric and I was able to sew without incident.

I usually make two or even three passes over the seam for extra strength. You could also back stitch or side stitch this area if you feel up to it.

And the completed fly after top stitching.

It’s time to complete the waistband with a polished-cotton lining. Begin by laying your trouser half and lining out, right sides down.

Lay the lining on the waistband, right sides together, aligning one end so that it overlaps the waistband facing by about an inch.

Holding the lining in rough position with one hand, flip the entire assembly over so that the lining is underneath. Begin basting at one end towards the other, keeping about 1 inch away from either waistband facing.

As you baste, allow the fabric to curve over your hand. This mimics the waistband curving over your waist, allowing the outside of the waistband to be slightly longer than the lining, helping to avoid any excess fabric in the lining.

Here’s the facing basted in place.

Flipping back over to the inside of the trousers, trim away the excess lining from the opposite end so that it extends about 1″ beyond the facing below.

Now begin folding under the lower edge of the lining so that it’s even with the waistband stitch line, or just slightly below it.

Baste this lower edge in place from end to end, keeping about 1″ from either end.

Repeat with the upper edge of the facing as well.

The results so far. Now to finish up the raw ends.

Fold under the raw ends, aligning them as you prefer in relation to the facing underneath.

Baste securely.

Here’s the lining after completing the basting process. Now you can work on the felling without worrying about things slipping out of place.

Fell along the entire lining using a small 1/8″ – 3/16″ stitch.

One thing to note that’s not pictured here (I think it’s in the video), is be sure to not sew closed your watch pocket while felling the lining. I like to keep a couple of fingers in the pocket as I work to ensure that this does not happen.

Continue around the ends.

And along the top edge as well.

This completes the lining and waistband installation.

Waistband Buttonhole

One last thing to do for the waistband is to add a buttonhole similar in size and position directly above the buttonholes on the fly. Be sure to work it from the outside of the trousers, so that the nice edge of the buttonhole is what is seen from the outside.

The rest of the watch pocket goes fairly quickly now that you’ve got the waistband and facings attached and pressed.

Cut a length of linen stay tape 4 1/2″ long and lay it on the linen stay about 1/16″ below the stitch line for the pocket bag.

Baste the linen tape to the trouser front.

Cross stitch the linen stay tape to the trouser front, being sure not to let the stitches show through to the right side.

Now fold the pocket bag over the linen tape, off-setting the seam by 1/16″ to 1/8″ behind the fold, hiding the pocket bag from outside view. Baste securely in place.

Top stitch across the pocket opening, catching the pocket bag underneath, using a machine stitch or a side stitch by hand. Keep the stitches about 1/8″ – 3/16″ away from the edge, so that they land in the middle of the stay tape that is sandwiched between the layers.

If using the side stitch, the needle enters the fabric just to the side of the previous stitch. On the underside, it is formed similar to a normal running stitch. The stitches should be 1/8″ to 1/4″ apart.

Here you can see the wrong side of the side stitches, catching the pocket bag and forming a firm opening for the watch pocket.

The outside of the watch pocket so far. I wish you could see the side stitches but they pretty much disappear into the fabric.

Take the remaining pocket bag half and press over the top edge 1/4″.

Open up the pocket and baste the pocket bag to the right side of the remaining pocket facing, 1/4″ from the edge.

Fell the pocket bag to the pocket facing. Remove the basting stitches.

With both pocket bag halves now attached, grasp both of them, being sure they are aligned properly, particularly at the pocket opening area. Baste across the top of the pocket facing through both pocket bag halves. This holds all the layers in place while we sew the pocket bag closed.

Draw out the seam lines on your pocket, 1/2″ from the edge. Be sure there is at least 1/2″ available on the underside, or you’ll end up like me with no room to turn under the raw edges. Add a couple of curves at each corner as well.

Sew the pocket bag closed, getting as close as you can to the waistband seam at the top without actually hitting it.

Trim the excess fabric from the pocket bag, leaving a 1/2″ seam allowance.

Carefully trim the pocket facing’s seam allowance to 1/4″ on each side, being sure not to cut the pocket bag below.

Fold the raw edges of the pocket bags inwards and press with your fingers as you go. The curved corners can be a little trick but you can perfect them as you overcast / fell the edges in the next step.

Fell or overcast the seam to the facings and along the pocket bag.

And with that the pocket is completed! We’ll tack down the ends of the pocket opening after the interfacing has been installed into the waistband.

One last detail, fold the side seam pocket bag back into place and baste across the top edge, just below the waistband. We’ll finish attaching this after putting in the interfacing as well.

With the waistband and pocket facings all basted into position, we can begin to sew everything down permanently. Begin by sewing the pocket bag to the trouser front using a 1/4″ seam allowance, beginning and ending precisely at the pocket opening marks. Be sure to keep the side seam pocket bag out of the way by folding it back.

Sew the pocket facing to the waistband in the same manner, using a 1/4″ seam allowance, keeping between the pocket opening marks. The stitching ends should line up as close as possible to those of the pocket bag.

Remove the basting stitches from the facing and pocket bag. You should end up with something similar to this.

Now sew the waistband with a 1/4″ seam allowance from the back of the trouser, to the third mark you made earlier.

Remove (for the last time!) the basting stitches holding the pocket in place.

Fold the side seam pocket out of the way. Baste down the waistband again if necessary.

Carefully sew the waistband to the trouser front from the rear pocket opening to that third mark (it’s just an inch or so), or as close as you can to the folded back pocket edge without actually catching it in the stitches.

Just before sewing, be sure to move the seam allowances of the pocket facing and bag out of the way. We don’t want them caught in the seam at all.

Ideally, the stitches should meet at the pocket opening mark. It turns out my seam allowance was slightly off when sewing on the pocket bag, so they met about 1/8″ apart. I’ll be able to make it work, but it’s not ideal.

Finally, sew the front end of the waistband using a 1/4″ seam allowance from the front pocket opening to the front edge of the waist. Be sure to move the seam allowance of the pocket out of the way again.

The seams lined up much better this time!

Here you can see how I’ve kept the 1/2″ seam allowances of the pocket bag and facing out of the waistband stitching.

You can see how I sew the waistband straight across the button catch rather than following the slight upward angle. It seems to align with the other half of the waistband just a bit better.

Pressing

With the wrong side of the trousers facing up, lifting the pocket so that the linen is exposed, clip the seam allowance of the trouser and linen pocket stay to the end of the stitch lines.

Press open the pocket bag seam as shown.

Now flip the pocket down into position, and press open the pocket facing seam.

Flip to the outside and press the inner pocket facing seam from the right side. It’s not really worth pressing the outside seam yet as the exact crease line has yet to be determined accurately.

Finally, press the remaining parts of the waistband seam up towards the waist as you did for the other waistband. This will enclose all the raw edges and make the seam stronger.

Adding a watch pocket to a waistband (usually on the right side) is not too difficult, but is somewhat involved with a lot of steps, so I will break the watch pocket into three sections. This first section will go over basting the pocket facings and waistband into place.

Besides the waistband, you’ll need the following pieces to construct a watch pocket. I like to make mine 3 1/2″ wide when finished, so all pieces should be cut 1″ wider, to give a 1/2″ seam allowance on either side. So for the pieces:

• 1 pocket facing 4 1/2″ x 1 1/4″
• 1 linen stay, 4 1/2″ x 1″
• 2 pocket bags, polished cotton 4 1/2″ x 4 1/2″
• 1 length of 1/4″ stay tape (not pictured) 4 1/2″
• Waistband

The pocket placement must first be marked – there are three marks total. The first two indicate the position of the pocket and are spaced 3 1/2″ apart (indicated by the two marks coming from the left). I like to place my pocket just in front of the hip bone so there is no interference. To the right (or towards the side seam, in other words), make a third mark an inch or two away from the pocket. You’ll be basting and sewing to this third mark, so it is fairly important.

Flipping to the wrong side, remove the basting stitches holding the pocket in place from the mark to the inside folded edge. Reinforce the basting at the mark with a couple of stitches in place if necessary.

Baste the linen pocket stay in place on the wrong side along the waist seam, flipping the pocket out of the way. Be sure to align it properly with 1/2″ allowance on either side of the pocket opening marks.

Baste the pocket back in place from the third mark to the edge of the pocket, keeping the stitches at least 1/2″ from the edge to give you some room to work with.

Baste the waistband into position in the same manner as the pocketless waistband, again keeping the stitches about 1/2″ from the edge. However, stop your stitching at the third mark, make a couple of stitches in place, and start a new thread to continue the rest of the basting.

I’m pointing here to the position of the third chalk mark, where I’ve started and stopped my basting stitches. This is so we can move and manipulate the pocket bag underneath without the entire waistband falling off.

If you made the side seam pockets earlier, this method will look very similar. Open up the waistband seam, exposing the right sides in between the layers. Transfer and mark the pocket openings on all pieces if you haven’t already.

With right sides together, place the pocket facing into position on the waistband. Be sure that 1/2″ allowance extends beyond the pocket opening marks on both sides.

Baste the pocket facing into position with a straight basting stitch, keeping the stitching out of where the seam will be sewn (1/4″ from the edge).

So far, you have the pocket facing basted right sides together to the waistband.

Now fold the pocket facing and waistband out of the way, exposing the right side of the trouser front underneath.

Place the pocket bag into position, right sides together with the trouser front, aligning it as you did the facing.

Holding the pocket bag half in position, fold the top of the side seam pocket that’s underneath out of the way.

Baste the pocket bag half to the trouser front, being sure not to catch the pocket that’s underneath. Mark the pocket openings.

This completes the basting process for the waistband and pocket facings. If you open yours up it should hopefully look similar to mine!

Finally, it’s time to attach the waistbands, which close up the top of the pockets, in a sense completing them. If you are planning to insert a watch pocket on one side, please see the next section on attaching the waistband with a watch pocket.

Lay the waistband, wide end at the front of the trousers, right sides together. There should be two or three inches of extra fabric at either end to turn back later on. Baste securely.

As you get to the center of the waistband at the side seam, you’ll have to full in a little excess of the waistband fabric to help it get around the curved seam.

As you baste, check to make sure that the stripes are aligned between the waistband and the front of the trousers. As you get to the back of the trousers, it becomes impossible to match the stripes due to the angle of the cut.

From the underside, make sure the basting stitches catch the pockets and all layers, and that everything lays flat.

Sew the waistband seam through all layers with a 1/4″ seam allowance from end to end of the trousers.

Now, when you get to the end of the waistband at the button catch side, I like to go straight across with my stitching rather than following the slight upward angle of the button catch. It seems to give a better fit with the left side of the trousers.

Press the waistband up. The seam itself is not opened, rather the seam allowance and the waistband should both be pressed towards the top of the trousers.

Around the side seam area I like to use a tailor’s ham since there is usually a bit of excess fabric here.

A final view of the underside showing the seam allowance pressed towards the waistband. This gives the strongest possible seam to the waistband.

It’s now time to attach the trouser fronts to the backs. Lay out the front on the table, and lay the back over the top, right sides together.

Now pin the very top of the side seam at the waist, ensuring that when we baste the side seam, the tops will be aligned properly.

Now, starting from the bottom hem, baste to the position of the knee (you can be precise about this and lay it out on the pattern, or just estimate).

Be sure to match the plaids as you’re going, if necessary.

Now baste from the knee to the waist, positioning the trousers so that the back piece is underneath and in an orientation that is most comfortable for your you.

As you’re basting, you’ll notice that the underside has a bit more fabric than the top side. This needs to be distributed evenly, moreso around the pocket opening, with the remaining excess distributed just below the pocket and tapering off to an even tension by the time you get to the knee.

When you get to the pocket, baste through all layers, ensuring the pocket notch is properly aligned 1/4″ from the edge.

It’s a good time to check how the plaids are aligned, and if necessary, redo them. Really depends upon how fussy you want to get. Also check that the pocket is properly aligned.

When you’re happy with how everything looks, sew the side seam using a 1/4″ seam allowance. Take care near the pocket area, as the presser foot has a tendency to skew off course due to all of the layers.

Remove the basting stitches, open the seam up, and press.

My plaids got slightly out of alignment here, alas. Hopefully yours turn out better!