I agree with Geri B.
"Make (200) 4" squares: Cut 20 strips width of fabric, then subcut each strip into 4" squares"
That way if my fabric is an odd width or I buy fat quarters or whatnot, I can make it work. Although I have to say, the worst pattern I've ever had was based on fat quarters. It said to cut strips from the fat quarters & then subcut equilateral triangles. I rarely buy fat quarters since it's nearly impossible to square them up. I spent an hour trying to figure out how much WOF inches I needed to cut into strips for each of the (15???) fabrics the pattern called for in order to make that 1,000 pyramid quilt. Never. Again.