Part 1 – Steps (1) to (5)
Part 2 – Steps (6) to (10)
(11) Turn the left leg the wrong way out. Insert the right leg into the left one, right sides together, and line up along the crotch seam. Sew the crotch seam by hand, using a buttonhole thread or at least a double thread, starting at the center back and stopping exactly at mark (3) – don´t catch the waistband interfacing at the center back. Turn the right way out and press open the seam allowances. Trim back the seam allowances from point (3) to the inner leg seam to about ¼” (7mm). Stitch the seam allowances of the left topside to the fly placket.
At first glimpse, lining the fly-shield seems a bit complicated, maybe the pictures here will bring more clarity. Fold the shield towards the topside, right sides together, and line up the lining with the seam allowance of the topside, the right side of the lining faces the wrong side of the fashion fabric. Sew in the ditch, starting at the top, until reaching the inner leg seam. Fold the lining around the seam allowances and again, stitch in the ditch.
Smooth out the lining over the fly-shield and turn in the seam allowance along the side edge, trim back if needed. When reaching the bottom of the shield, lead the lining towards the inner leg seam, covering the raw seam allowances of the crotch. Fell stitch in place. My lining was a bit too narrow at the bottom, so the tape is showing.
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