Before those two rules, I would put: * look at (and fill) the edges of the frame. Too often, we look at the part of the picture we are interested in (often th

Before those two rules, I would put: * look at (and fill) the edges of the frame. Too often, we look at the part of the picture we are interested in (often the center), and ignore the empty/ugly space around it. Look at the edges, and the center will take care of itself.