Cut three 17-inch lengths of ribbon. Pin one ribbon length 3 inches from a long edge of the bag fabric; sew in place. Overlap the first ribbon length by 1/16 inch and sew a second ribbon in place. In the same manner sew a third ribbon length. Sew scroll gimp along the top edge of the third ribbon.
With right sides together and aligning trims, fold the trimmed fabric in half widthwise so it measures 8-1/2x10 inches. Sew together the side and bottom with a 1/2-inch seam allowance. Press the seam allowances open. Trim the corners and turn the bag right side out. Fold and sew the lining piece in the same manner, leaving a 3-inch opening in the center bottom for turning; do no turn the lining right side out.
Cut a length of gimp for a shoulder strap. Pin each shoulder strap end to the wrong side of the lining at each seam; sew ends in place.
Slip the bag and shoulder strap inside the lining with right sides together. Using a 1/2-inch seam allowance, sew the bag and lining together along the top edges. Pull out the bag and shoulder strap through the opening in the lining. Hand-sew the opening closed. Tuck the lining into the bag, press the top edge, and topstitch through all layers 1/8-inch from the top. Sew a heart-shape bead to the green ribbon and gimp trim.