Things You'll Need
Instructions
Measure the length from the waist, up over the shoulder and down to the other side of the waist. Since the elastic stretches, cut minus 2 inches from that length. You will need two pieces of elastic.
Measure the fabric 1 1/4 inches wide, and the previous step's measurement lengthwise. Cut the fabric out. Do this twice, once for each suspender.
Use the suspender pattern to cut the denim. You will need four pieces that the buttons attach to for the suspenders. For each suspender piece, sew an edge seam on each so that the material doesn't unravel. You can also use a topstitch if the pieces will be decorative, but usually they are mostly hidden from view by the trousers. Sew one button onto each end of each strap. The buttons should be large enough to hold the weight of the elastic. Be certain that they will fit into the button holes on the trousers before sewing onto the pieces.
Fold the fabric so that the correct side (the side that will be visible once the suspenders are worn) is on the inside. Pin the long edge and sew a seam 1/8 inch near the edge of the fabric. Be certain that your stitches are close together and straight. This fabric will serve as a lining for the elastic, so that elastic itself is not visible. Turn the fabric correct side out once the seam is sewn.
Insert the elastic into the fabric tube and sew the ends to the fabric. The suspenders will be slightly stretchy since the elastic is folded over and sewn. Place the button strip onto the end and fold the end of the suspender over it. Sew a very strong double stitch to keep the strips in place. Do this for all four ends of the two suspenders.