Sewing things together is often seen as One Of Those Things that knitters and crocheters hate doing, because come on! It's not knitting! (or crocheting), and that's the stuff we really want to be doing. I admit, I also hate sewing, but because I like the finished product I do resign myself to sewing once in a while.
So at the end of last year when I was figuring out how I wanted this blanket to come together, I tested all kinds of joins. I didn't want to do a join-as-you-go style because I wanted this to take a year and JAYG takes less time than making and joining squares as separate steps. I didn't want to crochet the squares together because that creates a seam--a ridge. And I didn't want a ridge every six inches. I have an invisible join that works pretty well, but it lays the edge of one square on top of the edge of the next, and doesn't show the joining thread. Since I wanted the join visible and the squares flat, that wasn't going to work either.
What I finally settled on was astonishingly simple: whipstitch. It shows a neat set of diagonal lines, it's totally flat, and it's really easy. Let me show you.
