I use a plastic under bed storage box too. I line it with newspapers and put an old towel
pr two on top. Then I throw in some of the wash cloths you can buy at Wal Mart. I think there's 20 in a package for 2 or 3 dollars. It worked real well. I then had a waste basket with a plastic bag in it and that's where I put the soiled rags and then just dumped in the washer.