I used this one:
http://www.quiltingboard.com/t-36303-1.htm
You can machine sew your back binding as she did, or I have also sewn my folded binding on at the same time as I sew the first front piece, then I hand stitch it down. But I have found this method to be fast and easy and I think it's stronger than the method where you use the backing fabric as the sashing in the front.
Cheers!
Rachel