Step 1: Supplies
1/4" wooden dowels
small binder clips
If you want to use wider or narrower ribbon, you may want to experiment with different sized dowels. Grosgrain ribbon can also be used and looks really cute. I generally use upholstery thread, but you could even use dental floss if you want.
Step 2: Wrap your dowel with ribbon
Step 3: Baking your ribbon
Continue wrapping dowels until you have several. Set them on a cookie sheet and bake at 250 degrees for about twenty minutes. Let them cool completely.
Step 5: Cutting
Cut the ribbons into desired length. These pieces are about four inches long and since I want the bows fairly full, I've used six dowels worth of ribbon.
ETA: Depending on the type of ribbon you use, you may need to seal the ends to prevent fraying. Acrylic ribbon can be sealed by holding the cut end near a flame briefly until it melts very slightly, or dab the ends with Fray Check. Some ribbons may be just fine if you cut at a 45 degree angle.