This week we studied Gestalt principles of integration. It is interesting to note how the mind seeks completion and closure, a direction to follow, and groups items based on likeness and closeness.
Chapter 7 of Creating graphics for learning and performance suggests interesting questions to evaluate the design of an interface (based on Lohr, 2000) and general interface design guidelines (based on Lynch and Horton, 1999, and Nielsen, 2000), which should be used a toolbox by every designer.