I still think I'd buy a pattern, or get one out of a book from the library. I don't have EQ or any other quilt software. I can figure the fabric for most quilts fairly easily. Because this one has so many colors and they are cut so small, it becomes more of a chore to accurately determine how much of each you color you need. Also, sometimes it's hard to find more of a fabric when/if you run short, especially if it's been a while since you bought it. In addition, scraps are not always used.
I've looked at some of the patterns on the internet (some free and some for $). They come in all sizes, shapes and color combinations. I've seen strips everywhere from 1 1/2 inches to 3 inches. The colors repeat differently in each quilt. The only way to know how much of which colors to buy is decide how you want it to look. Once you've made a decision on what it's going to look like, you'll have figure the yardage yourself or use a commercial pattern.
This is an already long post, but I have to add that I planned to make a Log Cabin quilt as my first quilt. I knew I wanted it done in blues and beiges. Actually, I had a pattern book, but didn't really understand how to use it. I couldn't figure out how much of each color to buy. So, I just bought a yard of this and a 1/2 yard of that. I still haven't made that log cabin, but I still have all those blues I bought.
Because of my experience, I would suggest either buying a used book on Amazon or borrowing one from the library. Figure out how to use it. They give you yardage information for each size. Or, look on the internet until you find one in the size, shape and general configuration you want and buy it. Most quilt patterns are $10.00 on the web.
JMHO
bkay