Recently on a trip to the coast, I decided to learn how to paint waves. It is not easy to paint such a transitory thing, so some of it comes from observation and some of it comes from memory. So I wanted to learn how the waves form and how they crash and reform, so that it would be easier to paint them at any given stage. I painted some watercolor sketches plein air and then away from the scene, tried to put down from my memory what I had observed during the day. Doing both on the same day definitely helped to commit them to memory.