I also look at the dots on the selvage edge. But if there aren't any, I bring Mother Nature into play. I used to be a hairdresser and that helps me. You may find a fabric that you don't like the print but you do like the colors in it. Often you can use that as your guide. I have often grabbed the shopping cart and headed to the batiks to see different colors that would meld and play nice and not use the fabric. Prints like different paisleys are great for this. Works for me. I'm sure there will be others with great ideas.