Sometimes leggings can get a bit stretched out after wear, or if you have lost weight, your once-loved leggings do not have a hope of staying up on their own. Leggings made from different fabrics, such as denim, cotton and even polyester, can be resized to make those once perfect leggings fit great again. The project does not require a lot of sewing experience and can be completed in less than an hour for someone new to sewing.
Turn your leggings inside out and try them on.
Pull the extra fabric toward the outside seam of each leg gently. Begin at the waist and work downward toward the ankle. Pin the extra fabric as you go. Leave enough fabric that the leggings can be removed comfortably. Try sitting down before taking the trousers off to make sure the leggings fit just as comfortably in a seated position.
Take off the leggings and place them on a clean working surface inside out.
Sew a new seam line just on the outside of the line of pins beginning at the waistline. Use a straight stitch if you are sewing by hand or a zigzag stitch if you are using a sewing machine. When you reach the ankle, turn around and sew back up to the top along the same seam line.
Remove the pins from the leggings and try them on inside out. If the leggings fit snugly enough, remove the trousers and cut off the extra material beyond the new seam line. Leave a little bit of fabric beyond the stitching.
Use an iron to fold over the little bit of fabric for a comfortable seam.