One way to keep a white sofa clean is to purchase a piece of furniture that comes with a washable slipcover. In addition, you can have a professional apply a stain guard on the fabric on the couch. Always have some fabric cleaner in the house, so you can take care of the stains while they are fresh. Cleaning the couch with a lint roller regularly helps keep the couch white as well.
Using a washable slipcover is convenient because you can wash a part of it without taking the cover off, for example, in case of a spill. At the same time, you can take the cover off the entire sofa and wash it in a washing machine to get rid of larger stains on the surface that appear from everyday use. You can purchase sofas with washable slipcovers from a number of stores, including IKEA and Pottery Barn. There are some non-professional stain guard products available on the market as well, but professional products usually give better results. If something is spilled on the couch and wiped off quickly, the stain guard can usually prevent a stain from forming.
It is important to have stain-removal products in your home because sometimes stains might appear even if the couch was treated with stain guard, for example, if you noticed the stain too late. Also, move the cushions around every several weeks to prevent spots from appearing in places where people sit on a regular basis.