Everyone uses body language during the interview (whether they realize it or not), but very few think about it in advance and modify their body language to produce the most positive effect. Body language is merely the smaller, less prominent nonverbal cues that we give others while communicating. Following are some typical interpretations of body language cues:
Your words tell me a story but your body tells me the whole story.
As you can see, there are far more negatives than positives—possibly more than we are consciously aware of. This list is given not so that you can artificially adopt the positive body language techniques, but more to help you recognize and avoid the negatives. If you have a habit of doing any of the above negatives, remove that action from your pattern of behavior before it sends the wrong signal. Concentrate on removing it now so you will not have to think about it during the interview.
And keep in mind the person on the other side of the desk. As you talk with an interviewer, be aware of (although not preoccupied with) their body language and nonverbal cues. Do not try to read more than is actually being communicated, but try to develop a sense of the interviewer's reception of you. The most obvious example is the smile connection—when your smile brings about a smile from the interviewer. Do your best to stay connected with your interviewer—both verbally and nonverbally.