Painting the interior parts of a residential or commercial unit may seem easier than it really is. Some beginners believe that painting interior walls is all about buying several cans of paint, opening the cans, dipping in a brush, and slapping the brush on the wall. Although your ideas about painting may not be as simplistic, it is possible to underestimate the importance of preparing your walls adequately, mixing your paint well, and using proper application techniques. It is important to consider a few interior painting tips before you open that can of paint to ensure you get professional results. First, cover everything. New painters often underestimate the ability of paint to spatter. Prepare your space with adequate amounts of dropcloths. Avoid using plastic dropcloths because they are slippery and tend to move around.