Cut your pocket into a square or rectangle. Cut strips of the scrap fabric to 1" width. Attach these scraps to the sides and bottom of your pockets.
Cut four lengths of contrast fabric, each the length of the zip and 2" wide. Put two strips right sides together with the zip in the middle of the sandwich and, using your zipper foot, stitch close to the teeth of the zip. Open out and repeat with the other two pieces of contrast. Then top stitch down the edge of the zip.
Fold the wrist strap in half and pin to one long side of the pocket pieces.
Fold in half along the zip and stitch around the three open edges.
Turn through the zip opening, pushing out the corners.