You may like to line the shorts for extra durability. Use double the same fabric or a mesh and simply double up the pieces as you sew.
Begin by laying the two SHORTS pattern pieces RIGHT SIDES together.
Pin and stitch the FRONT and BACK centre seams together.
Trim and finish the seam allowances using zig-zag stitch or an overlocker stitch.
Use zig-zag stitch or other stretch stitch throughout this project. Also ensure to use a ballpoint jersey machine needle.
Open up the FRONT and BACK crotch, Lay the GUSSET RIGHT SIDES together with the FRONT and BACK.
Pin, stitch and finish the seam allowances.
Cut the length of elastic to match the same length as the WAISTBAND pattern piece.
Match the two shorter seam allowances from the WAISTBAND RIGHT SIDES together.
Stitch and trim the seam allowance.
To secure the elastic, instead of sewing the seam allowances RIGHT SIDES together, overlap one seam allowance onto the other then sew. This will avoid excess bulk in the WAISTBAND.
Fold the WAISTBAND in half lengthways. Match the raw seam allowances to the waistline of the SHORTS. Insert the elastic between the folded WAISTBAND.
Match the seam line of the WAISTBAND to the BACK seam line and ease the rest around.
Pin stitch and finish the seam allowance ensuring not to sew through the elastic.
Finish the seam allowances of the leg openings using zig-zag stitch or an overlocker.
Fold back the seam allowances of the leg opening to the WRONG SIDE and top-stitch with zig-zag stitch to secure.