My fun in doing the sampler 12" blocks, assuming each one is different, I like the fat quarters you get at the fabric shop. I finished a sampler a few weeks ago with 35 12" blocks and I did not use the same fabric twice. I just picked out fabrics that were and or used to be fat quarters (that I saw and liked and absolutely had to have it). I like to get the 99 cent fat quarters at JoAnn's. It is a great variety you can use and it really is a lot of fun. To this day and I have been quilting a long time, I do not know how much fabric you need. I just use what I have and when I don't need it, that's when I get the fat quarters. Lifts the spirits and keeps the stash well fed. Edie