Here's one...
https://www.etsy.com/listing/1500402...s_manager_grid It gives instructions for squares (Windows) and rectangles (Brick Work). I've made a few and they turn out great with minky for the center squares, and flannel for the outside, with or without batting. I've done them with denim and flannel, and flannel and regular cottons, too. The edge of the flannel is raw, and sewn down with a zig-zag, but not a satin stitch. They work up pretty quick.