Originally Posted by Jeanne S

I have "prewashed" smaller pieces of fabric like that lots of times. I just fill a large bowl or sink with HOT water and let the fabric soak an hour or so. I think sometimes I have added a bit of detergent and swished with my hand too, but not necessary. I then dump out the water, let the fabric drain till it is not so heavy and drippy, then just put them over hangars and let drip dry. I think your plan will work great.
I think hand washing like this is best for small cuts and strips to avoid lots of fraying, flannel and regular cotton.