Better late than never (and I’m only slightly late), here’s my finished Granny Squares project:
I’m really glad I took the time to add the 4th strip of squares – it was really narrow before, and I think it looks much better now. I joined the squares with slip stitch because I liked the ridged effect, and I bordered it with a row of single crochet all around the edge – the design is already busy enough, so I thought I’d keep the edging simple.
Here’s a close-up:
See how the square is exactly the same size as the width of the top of the chair? I was hoping it would work out like that!