Fold the sides, top and bottom of the fabric again. Press all folds. Lay the blind, right side down, on a flat surface. Lay the lining, wrong side down, on top of the blind positioning it level with the top of the blind and centrally across the width of the blind. Pin the lining into position.
Hand slipstitch the lining in position along the bottom and both sides.
Take care not to catch the front fabric of the blind in your stitches. Pin a strip of Velcro along the top edge of the blind and machine stitch in place. These lines should divide the blind width into 4 equal segments. Sew brass rings into position at each of these points. Cut 3 lengths of cord each measuring 1.5 times the length of the blind plus the width of the blind.