Aestheticians are always learning about new ingredients, creating new seasonal menus of services, and building custom skin care routines for clients. One of the first things taught in an aesthetic program is how to do a patch test. When a client comes into the spa, it is important to do a skin consultation to see what type of skin they have, what products they are using, and any allergies they may have. Patch tests are an excellent way to be sure that the product will work for a client and that they will be comfortable.