How do I sew a fly-front zipper?
Beginning about 1 1/2" from the inseam, stitch the front crotch seam to the zipper opening lower edge; backstitch. Baste the remainder of the zipper extension closed (Figure 1).
Stitch front crotch seam; baste fly opening closed.
Note: The following directions are for a woman's fly. For a man's garment, reverse the directions.
Clip stitching at zipper bottom; press open.
Right side down, place the zipper on the left fly extension with the zipper tape edge along the basted seamline and the zipper stop just above the backstitching. Stitch the left zipper tape close to the zipper teeth (Figure 3).
Stitch left zipper tape close to teeth.
Fold the left extension under along the stitching line, exposing the zipper teeth and press. Edgestitch the fold next to the zipper teeth (Figure 4).
Edgestitch fold next to zipper teeth.
Open out the right fly extension. Fold the left extension and zipper right sides together with the right extension and press flat. Stitch the right zipper tape to the right extension (Figure 5).
Stitch zipper tape to right extension.
Turn the fly extensions into place on the pant right front and press into place. Baste in place through all layers. Mark and topstitch the fly (Figure 6). Pull the threads through to wrong side at the zipper lower edge and knot to secure. Remove all basting stitches.