The C.R.A.P. Model
The C.R.A.P. model consists of the four most important principles of document design. Including each of these principles throughout your design will help you create an efficient and effective document. C.R.A.P. is an acronym that stands for: Contrast, Repetition, Alignment, and Proximity.
For more information and samples, click here (see section 5.8, The CRAP Test).