I press at each and every step. I learned to have a neat top every seam had to be pressed before you sewed over top of it again. A good finger pressing will work but I prefer to use the actual iron. I simply wouldn't think of doing it any other way. I have worked on group quilts. I wasn't Speedy Gonzales because of my attention to measuring and pressing details but then my sections actually ended up the measure they were supposed to be. I also believe the attention to detail helps to keep a quilt square and minimizes lettuce edges.