Howto: add simple, invisible pockets to skirts and dresses
Annika Victoria presents a simple method for adding pockets to skirts and dresses – providing the original garment has a sideseam, the new pocket will not show (unless, that is, you fill it with bulky things).
1. Trace your hand, with fingers together, on a piece of paper. Leave about a one-inch gap around your hand. Cut out the outline. This will be your pocket pattern.
2. Fold your pocket fabric in half, then cut out the pockets using your pattern. You should end up with four pieces of fabric.
3. Turn your dress or skirt inside out and use the chalk to mark where the top of your pockets to be. Place your fabric along the seam and mark where your pocket should end. Rip the seam starting one inch above and below your marks.
4. Pin each piece of pocket fabric to a seam side (see 02:10 in the video above for a demonstration). Essentially, you’re pinning each side of the pocket to the seam you just ripped to create the top of the pocket.
5. Sew the one-inch seam gap closed at the top of your pocket, the edges of the pocket together, and the one-inch seam gap at the bottom of your pocket.
https://boingboing.net/2017/01/09/howto-add-simple-invisible-p.html