On the sample pattern, I counted 80 stitches by 18 garter ridges in each color, or 1440 knit/purl combo stitches, took the square root and got 37.8 stitches, so my squares are 38 stitches long ,working out just right.

I had enough yarn for each square, and the grafting between the purple and orange squares went well.

Around the whole blanket, I picked up stitches into each garter ridge, plus one extra at each corner, am now doing garter stitch in the round using a Knit picks interchangeable needle set along with 2 40” cables with a connector. It’s slow going as I have to smooch along the knitting to go around the cable, but it is working, and no cables have broke (up to now).