Appearance is the strongest non-verbal cue in an interview.
The best guideline for appearance is to present yourself in a manner that is consistent with how most employees currently present themselves on the job. Gestures and facial expressions also help you communicate without talking. Lack of interest is displayed by fiddling, monotone voice, and poor eye contact. Being prepared may give you the necessary self-confidence. Have neatly groomed hair and DO NOT overdo make-up, jewelry, or wear aftershave or cologne that will linger after you leave the room.