Foam brushes make controlling where the paint goes easier than normal bristle brushes. Foam brushes also eliminate a lot of the brush-stroke look that appears when a corner or piece of molding is painted. There is no one set method on how to use a foam brush, however there is one sure-fire method for all applications. Foam brushes are relatively inexpensive and are designed to be thrown away after one use. It is also possible to re-use them if necessary.
Pour or mix your paint into a cup. Cups can be held in one hand while you touch up a surface. Sometimes while using a paint roller you may encounter a space too small to reach and you may also dip your foam brush into this space.
Dip the tip of the foam brush into the paint. You should only go up to the end of the triangular tip.
Twist the brush as you lift it from the paint. This will collect all excess paint on the brush.
Stroke your surface gently with the brush. Practice a stroke-lift-stroke-lift style. Stroke in one direction. If you stroke too hard, you make a deep groove in your paint surface.