I build layers with paint, like thoughts in my mind or the passing of time.  One occurs, then the next, repeating until only bits of  what was beneath remains.  Sometimes what was one thing becomes another, sometimes multiple layers merge to become entirely different than their origins. Most of my work is not premeditated, I start a piece without knowing how it will end up.  As I paint I see it.  Some pieces are done after two or three layers, others require more.  One of the hardest parts for me is knowing when a piece is done.