the number of fabrics and width of strips is determined by the pattern you want to produce in the final top. Skinnier strips help make sharper "turns" in the pattern, wider strips give straighter line and shallower turns. I would think you want to find a simple pattern first, or make up a simple one to test on your first attempt. Here's one free bargello pattern that I found by googling "free bargello quilt patterns". Good luck
http://www.docstoc.com/docs/1076764/...Quilt-Patterns