Forgot to tell you... I was taught by a master quilter to cut long long strips of binding from the length of the fabric, before I cut anything else!
This has these advantages:
It might be long enough to go around the quilt with no piecing!
It will iron straight easier...and it will track straighter through the sewing machine.
If you are hand stitching, it will fold straighter and stay in place with fewer pins.
It will make a straighter edge, without ripples, because it does not stretch.