If you made a quilt sandwich that is the size of all eight mats your need and drew the squares on the sandwich it would give you opportunity to quilt something different in each square. Cut them apart with your rotary cutter and you will have straight edges and square corners to bind. If you try to do intricate quilting (practicing FMQ) on eight inch squares you will not be able to keep them square and easy to bind. Generally, when people make pot holders the quilting is very simple-lines or crosshatching. They are most often made a little larger than the finished size and cut down to facilitate binding.