Rule #2 - Speak with one visual voice

"Make all parts talk to each other…in the same language. Take a look at everything, from the big picture down to the tiniest detail, and ask yourself: “Does everything relate harmoniously to everything else?” Good design assumes that the visual language of the piece-its internal logic-is resolved to address all of its parts so that they reinforce, restate, and reference each other, not only in shape or weight or placement, but conceptually as well. As soon as one element seems out of place, or just a leftover that hasn’t been given any thought, it disconnects from the others, and the message is weakened." Design Elements: A Graphic Style Manual, Stratham