Dawn Dugan specializes in writing books, articles, white papers, reports and special communications for the human resources industry. She is the co-author of Effective Executive Compensation, which was published by AMACOM in 2008. Read more...
Watch your interviewer's body language, and mimic it when appropriate.
If your interviewer leans forward, then you lean forward. If he or she smiles, reciprocate. This not only conveys respect, but indicates you're "on the same page."
Pay attention to negative body language as well. If the interviewer indicates boredom by drumming his or her fingers on the desk, or by gazing at the wall in back of you, you might want to work on ramping up the interest factor.