So I spent an hour sometime last week, cutting out the pieces for the back.
I marked the places for the buttons with a blue cotton yarn.
Today, I spent an hour sewing. I'm using 1 inch seam allowances. The fabric is nice and stretchy so I was able to ease the seams where I needed to.
Some of the seams are zig-zag. (So that the seam stays in the fold between the tufts.) I'll post a photo later. One of those points gave me a big problem, and it was hard to rip out... I left it until tomorrow....