I do sew the miters on the corners - just a couple of little stitches or just run through the middle of the corner - I always sew the binding on the front then hand stitch the back - However, with potholders I usually machine bind those - I really don't worry about the threads showing on the back - another tip is to use thread that matches the back of your potholder so if the seams do show - they will blend in better.