It's simple, you go to fabric creation and you get to choose from hundreds of templates; then you have five options for the size of the pattern, then you get to pick from a very large variety of colors. Some other websites only had one yellow, one blue, etc. It's about $18 a yard which, after doing a lot of research, I think it's worth $18. I found fabric as high as $200 a yard in fabric stores.
There are other websites that allow you to upload a photo or graphic to create custom fabric, I am also very intrigued by this but don't know that I currently need to go that custom for my wedding fabric. I hope to order mine soon and will report that outcome.