When I cut and how much I cut in advance depends on the project. If it's a sampler quilt, with all different blocks, I cut one block at a time. If I need to make multiple copies of the same block, I cut all those blocks at once and then sew them. However, if I have the same block in different color settings, I usually cut only one color setting at a time. All of that is how I cut when piecing by hand. It keeps me from getting confused and messing up my blocks. When it comes to machine quilting, that's usually done with strip sets (at least, at the level I'm machine quilting now) and then I cut all of my strips in one go.