Verbal communication - is very important in demonstrating your qualifications.

• Use active verbs to describe your qualifications.
• Time is limited, be clear, concise, and complete but don’t make the interviewer drag information from you.
• For strong and effective responses: 1) support your statements with specific examples; 2) share your role in an activity; 3) discuss the outcome of an event or solution to a problem as the result of your involvement; 4) summarize your experiences to emphasize your strengths.
• Be positive.
• Ask questions- it shows that you've done your homework and demonstrates initiative and analytical abilities.

Non-verbal communication - your body language and affect tell a lot about you. Use them to your advantage to convey self-confidence, sincerity, enthusiasm, and capability.

• Dress appropriately for the type of job/organization you are applying for. When in doubt dress conservatively. Don't wear heavy cologne or perfume.
• Offer a firm handshake. Extending your hand and introducing yourself first instead of waiting for the interviewer shows that you take initiative.
• Eye contact should be open and direct, especially when listening or speaking.
• Posture should be relaxed but upright (not too stiff), facing straight on. Know your nervous habits and practice controlling them (i.e. jiggling foot, cracking knuckles)
• Hands can be use in a relaxed way to communicate animation and excitement about ideas.
• Use facial expressions to convey interest and sincerity (i.e. smile, nod).
• Voice tone should be moderate and well modulated. Avoid speaking too softly or in a monotone.
• Be an active listener - show responsiveness to the interviewer, communicate interest.
• Convey enthusiasm - show that you are interested through your actions.
• Be confident- believe in yourself (or at the very least make the interviewer think you do). Remember that the main subject of the interview will be you, and if you've done your homework, that's one subject you know best. However, don't come across as arrogant.