Once the watercolors are all dry, then this is when you get out all your Twinkling H2Os and play. You can highlight the colors that you already have or make some of the more neutral colors pop out. I usually use H2Os in pretty much its full vibrant colors. I just add a little water to get it going. You can't see it here but the H2Os shimmer and shine when you move it in the light. You don't want a dull wash here of H2Os.