Use bits and bobs you dont need to make one of the most useful things in your school bag!
Cut the fabric slightly longer than your zip length ways and you decide what looks best width ways by folding it in half.
Stitch to the zip, and stitch the the edges. I folded over the side of the fabric and stitched that on because it looks good with a ribbion through it.
Make holes through your doubled over edge(if you have one) and pull a ribbon,lace,wool whatever you like through.
Nows the fun bit, adding the junk!
I stitch on a patch, some groovy looking fabric scraps, some beads, a safety pin with some charms, badges and some plastic toy pieces(ello rocks!)