In the 5 yrs that I've worn minerals, I've found that it is possible to over-buff. With time, practice and patience you will be able to tell when the minerals adjust. Whether or not to buff depends on the finish that you desire. When you apply wet you are creating a liquid foundation--heavier coverage. If you buff afterwards, you will remove some of the minerals. This is fine if you've applied too much and wish to remove a layer, but be careful because it will change the finish of theses areas. It will provide a more "natural" appearance. When applying wet, use just enough moisture to create a very fluid paste. If the minerals seem cakey and unnatural, you have applied too much. Remember, you only need a thin layer.