I just came across this great article by Melissa Wolck at Greenhouse Fabrics………
Here it is:
Designing with pattern can be a little intimidating. There are so many styles to choose from, in addition to endless varieties of scale and color. A general rule of thumb for mixing fabric patterns is to select one large, one medium and one small scale, but that’s just a standard formula, not the be-all end-all. Coordinating several small scale patterns can create a lot of visual interest.
Here are a few things I like to consider when designing with patterned fabrics.