Choose desired color of 1 1/2-inch to 2-inch wide grosgrain ribbon and cut desired number of pieces of ribbon to desired length of bag plus 6 to 12 inches to allow for overhang on either side.
Stack ribbon over foundation fabric of choice, layering as you go, to determine height of bag.
Measure and cut foundation fabric based on ribbon layout. The length should be double the height of the layered ribbon plus 3 inches (to leave 1 1/2 inches at top of bag) and the width should be the desired width of bag plus 1 inch (leaving a 1/2-inch seam allowance on either side). Fold fabric in half and iron to create crease to act as bottom of bag.
Pin first strip of ribbon into place. The bottom edge of ribbon should run along bottom of bag.
With sewing machine, sew a straight stitch across the top of the ribbon, starting and stopping stitch 1/2 inch from either edge of foundation fabric.
Repeat process, sewing ribbon in layers up side of bag, stopping before adding last length of ribbon.
At top of bag, fold over and iron edge of foundation fabric twice (approximately 3/4 of an inch each time). Cut piece of ribbon the length of the width of the foundation fabric and pin inside of bag along folded edge.
To make handle, measure 18 inches of ribbon, sew in half at the middle, and pin to inside of bag and 2 inches from each side edge.
Pin final ribbon layer on outside of bag and sew across the top edge, securing inside ribbon, handles and outside ribbon layer into place, all at once.
Repeat steps 5 through 9 on the other side of the bag.
Once all ribbon is sewn into place, fold bag in half, right sides out and using masking tape, tape back all overhanging ribbon pieces, exposing 1/2 inch of foundation fabric on either side edge.
Pin sides of fabric together and with sewing machine, sew 1/4-inch seam. Trim edge of seam to about 1/8 inch and turn bag inside out.
With an iron, press side edges and sew along interior seam to reinforce and give a clean outer edge. Turn bag right sides out.