For each section of the painting such as the sky, water, foreground, etc., I’ll have a separate palette. For example, on the palette at the top of this picture I’ve mixed up a blue for the sky . Along with that, I’ve added some Cobalt blue, red and white to give me all the variation I need to modulate the sky from light to dark. On the second palette I’ve mixed a warm and cool grey that will be the base of the cloud structure.