Describe in detail the common courtesies and body language an interviewee should display to create a favorable first impression in an interview.

Answers will vary. Common courtesies and confident body language can contribute to a favorable first impression in the early moments when you have not yet had an opportunity to talk about your qualifications:
a. Use the interviewer's name, and pronounce it correctly. Even if the interviewer calls you by your first name, always use the interviewer's surname unless specifically invited to do otherwise.
b. Apply a firm handshake. Usually, the interviewer will initiate the handshake, although you may do so. In either case, apply a firm handshake. You do not want to leave the impression that you are weak or timid. At the same time, you do not want to overdo the firm grip and leave an impression of being overbearing.
c. Wait for the interviewer to ask you to be seated. If you are not invited to sit, choose a chair across from or beside the interviewer's desk.
d. Maintain appropriate eye contact, and use your body language to convey confidence. Sit erect and lean forward slightly to express interest. For a professional image, avoid slouching, chewing gum, and fidgeting.
e. Be conscious of nonverbal messages. If the interviewer's eyes are glazing over, end your answer, but expand it if they are bright and the head is nodding vigorously. If the interviewer is from a different culture, be conscious of subtle differences in nonverbal communication that could affect the interviewer's perception of you.