Here's the process. The first step is cutting the afghan up into totebag sizes. Here's a picture of the pieces as I cut them. I had enough for two of these cross-shaped pieces. The narrow strips going out each side become the sides of the bag.
The most boring part was to very carefully, in excellent light, snip the yarn connecting the different sections together. I wanted my edge to be just the squares themselves. No scalloped edge or other connecting threads. Doing this for both bag pieces plus the leftover squares I'm going to use for messenger bags took FOREVER.
Once I had the threads snipped, I laced up the sides of the bag. I've done this on my machine before, but the wear and tear sewing on such thick fabric is not worth it. I couldn't get a good picture of the lacing, but it came out nice enough that I kept it on the outside, finished side of the bag!
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Here's a shot of the lining. Valori Wells "Hoot." Very colorful with fanciful trees and flowers plus a couple of birds thrown in. The pocket is just plain brown. I didn't want any pattern to compete with the print.
All in all, a great project. I'm only sorry I had the afghan for 6 months before actually doing it!