Stage 3: I've started painting in the sand and rivulets of water running down from the boulders at the top of the beach. The sand is painted in three subtly different shades of brown while the water, which is reflecting the boulders and the rising escarpment behind (out of the picture), is painted using a further three or four darker browns. It is critical at this stage to get the colours right and I'll spend several hours mixing colours and trying them out together on small areas of the painting until I'm happy with them. These test-dabs of paint are simply wiped off before proper painting begins.