LuLa.: Bandana Bib Cut two pieces of fabric, one for each side into an isosceles triangle , the long side measuring 17in and the two shorter sides measuring 12in. Sew them together, right sides facing in as you would a pillow case, leaving about 2in on any side open so you can turn it right side out. After turning out, poke the corners out, fold and pin the open 2in, then iron. Sew around the entire perimeter, about 1/8in in from the seam. Attach some snaps or velcro, and voila!