Remember confidence is the key to success, if you converse confidently it will surely impress your interviewer. Always greet your interviewer with a firm handshake and a smile. Make eye contact while talking to the interviewer. Keep in mind that you have to sell yourself before you get to sell anything else and if you fail to convince your interviewer that he needs to buy you in the first thirty seconds then the rest of the interview will only be a time wasting event.
Prepare well by doing your homework before the interview. It is always wise to re-read your resume and the job advertisement beforehand. Have some backhand information about the company which can easily be obtained by visiting their web site. Know what salary you want as you will be asked about your expected salary package.
Do not get confused or even if you do, keep calm and do not let the interviewer know what is going inside your head. Try to answer all the questions properly. Do not rush yourself as it is better to take your time while answering the questions.
It is wise to talk about your experience, abilities, skills and knowledge. It is completely up to you to convince your potential employers that you are the right man/woman for the job.
Always carry a positive approach as your interviewer would not want to be working with someone who is negative minded and talks ill of his colleagues behind their back. Companies like to hire self motivated and enthusiastic people who enjoy a challenge.
Body language is another very important tool in getting you through an interview. Always sit upright and do not fold your arms or look down on the floor. Remember to use your hands when making a point in order to nail an interview.