How to keep your makeup brushes clean?

Thinking of makeup without good brushes is simply impossible. Brushes make the entire makeup procedure simple and convenient. But how many of you really wash and sanitize the makeup brushes before using them. I suppose very few of you clean the makeup brushes and I am sure some might not even know that they can be washed (my little sister was astonished when I told her that brushes can be washed). I know it sounds strange but is true.