Here are a few patterns. When you need a pattern, search online with the name of what you are looking for and add pattern (do-rag pattern). Hope these are what you're looking for.
http://www.sewersforum.com/photogal/cancercap.pdf
http://itsmybag.myeweb.net/photo3_2.html
http://fosteringlove.tripod.com/id12.html