Show your work to the person you are presenting to, and not to yourself. Don’t position your work in such a way that you have a clear view of it, but the interviewer has to crane his or her neck to see it.

Unless you are sitting side by side with the person interviewing you, this is disastrous. Your work should be placed directly in front of the viewer, and not sideways. It’s glaringly obvious, but the number of young designers who commit this error is staggering.