Joe, everyone has their preference, but average binding is cut 2.5"s - folded in half and pressed flat, then sewn on one side of your quilt . . . . I square my quilt up before putting on the binding. Once sewn down on one side, fold the binding over and either hand sew or use a decorative stitch to finish the binding. A nice folded binding is thicker so you don't end up with the binding falling apart from handling the quilt, but you end up sewing through 5 layers. You have the top, batting, back, and the folded in half binding. When you finish sewing the binding on the second side of your quilt - your binding should be 'full' of quilt edge!
Nancy