Things You'll Need
Old pair of underwear
Making your own clothes can be very satisfying, but many people do not realize that they can even sew their own underwear. Underwear can be made out of any stretchy fabric in any color or pattern. You can even make them from an old t-shirt that you don't wear anymore but don't want to throw away. Follow these steps to start making your own unique underwear.
Find an existing pair of underwear that fits well and that you don't mind cutting up. You will be using this as your pattern. Carefully cut off the elastic at the waistband and around the leg openings. Do not throw this elastic away as you will need it later. Cut along the side seams of the underwear then remove the lining in the crotch and cut the bottom seam. You will now have three pattern pieces.
Lay the three pattern pieces flat on top of the fabric that you'll be using to make the new pair of underwear. Pin the pieces to the fabric and cut carefully around the edges, taking care not to stretch or distort the fabric while cutting it. You will want to cut out one of each pattern piece.
Place the front piece of the underwear right side up on your table. Place the back piece on top of it with the right side facing down, and then place the crotch lining panel right side down on top of the back piece. Line up all three pieces at the crotch seam and sew them together, then sew the two side seams, leaving a 1/4 inch seam allowance.
Fold the crotch lining piece up so that it's against the front piece and iron it down. You can then stitch down the other end of the lining to attach it to the front piece if you choose, but this is not mandatory. Most commercially made underwear leaves one end of the crotch panel unattached.
Use the elastic that you cut off the existing underwear earlier as a guide to determine how much elastic you will need for the leg openings and waistband. Cut out the three elastic pieces. Starting on one side of the waistband, begin sewing the elastic to the right side of the underwear, as close as possible to the edge of the fabric. Use your sewing machine's zigzag stitch setting, which allows for much more stretch than a straight stitch does. Sew elastic all the way around the waistband and then do the same on each leg opening. Backstitch at the beginning and end of each seam to prevent the thread from unraveling.
Fold the elasticized edges over to the wrong side of the fabric and then zigzag stitch all the way around the waist and each leg opening again. This creates a hem so your new underwear won't have raw edges and also makes the elastic only visible on the inside. Once this step is complete, your new underwear is ready to wear.
You can take the three pieces of the old underwear and trace their shape onto paper to make a more traditional-looking paper pattern.