Maintain good eye contact and smile when appropriate. Be enthusiastic and responsive. Sit comfortably, without slouching. Keep your clipboard, note pad, briefcase, or portfolio on the floor beside your chair for easy retrieval when necessary. Respond to questions specifically and concisely but give sufficient details to enable the interviewer to evaluate your credentials.
Interviewers become frustrated when they have to listen to long rambling answers.
Think before you answer. It is quite acceptable to pause before speaking in order to organize your thoughts, but think quietly. Avoid verbal fillers such as um, ah, you know, etc., or repeating the question in order to provide thinking time. Use business language. Prepare in advance to talk about any topic that you are concerned about.