What you’ll need: A bleach-free cloth you can wash with soap and water, preferably in a bleach-proof container, a dish towel or other soft material to wipe off excess, and a cloth bag for wiping away spills.
To use: Mix bleach with your regular bleach and water.
Wash your cloth according to directions on the container.
If your cloth becomes soiled or smells, rinse again.
When you’re done washing, throw the cloth away.
For more information: http://www.harrypotter.com/wp-content/uploads/2016/02/Hair-Bathroom-Cleaning-Product-Beverage-for-Knit-Cloth.pdf