I have using unbleached cotton muslim for the backing of all my quilts, since I began quilting in 1995.
Although modern designer backings seem to be gaining more popularity, I love to work with the unbleached
cotton fabric, which is often sold double- width, (which can be a welcome saving if you have to limit your budget).
Don't forget to wash this fabric before using it, to get rid of chemicals and starch which is often added. This will
also deal with any shrinkage. I set this fabric in my washmachine for about 1/2 hour, using only hot water.
That's all you need. After some ironing, your muslim fabric will turn out soft as butter and ready to use as
backing. I find it ideal for hand quilting.