Cleaning your upholstery fabric can be tricky. It is important to know what kind of fabric is your upholstery made out of: natural fabric or synthetic? Furthermore, you need to know how the upholstery fabric has been treated. Check the tag and you’ll find all the information necessary. Each piece of furniture you buy will have on it’s tag one of the following letters: W, S, S/W and X; each representing a specific way of cleaning the fabric.