I usually sew one block first. Then assembly line sew for that block section. Then after all the sections are assembly lined I finish up those blocks. The assembly line the other blocks or sections if I can. Then assemble that block or section. But I always make a block section first so I know I am sewing according to the directions and the way I want the block to work. Also another real good reason to use a design wall when its complicated doing one section at a time. The most important thing is that we enjoy the process how ever it works for us. Happy Quilting!