What size quilt are you wanting to end up with? I always start there and work backwards, although math and I are not friends. I do a lot of scratch work on paper with diagrams and stuff and calculator if I must work it out myself. But I would certainly go on a major hunt to find that pattern online first .I'd gladly pay $10-15 for one that didn't make me figure out the math. I figure the time I save, and the time they put into to do that math, is worth it. That said, I've only bought one pattern ever, because I tend to "wing it" on my own with simple patterns, pen, paper...