If you are hand stitching the binding to the back after stitching it on the front....Don't trim away the excess batting and backing. Line the edge of the binding with your top and machine stitch it on. Then take it to your cutting table and trim leaving a little more than you think you need. When you roll the binding to the back to hand stitch, the binding should be nice and stuffed full of batting and fabric. Not so much it's hard to stitch just full. This is one thing a quilt judge will look for. Even if there are no quilt police the judges look for this for a reason. A full binding will wear less than one that is not full,