First impression lasts. It is more true when it refers to how you look: hairstyle, clothes, shoes, etc. Make sure you are completely neat, dressed properly for the interview and smells nice. Never go to an interview wearing just a t-shirt and sporting a long and unkempt hairdo.
Don't Come Unprepared
Make sure your resumé is error-free and that you have enough copies should the interviewer request for more. Research about the company you're applying for. Knowing something about them increases your chances of giving the appropriate or best answers during the interview.
Don't Lie
What you wrote in your resumé and the things you say in your interviews should all be the truth. Don't lie about previous employments or education you had. These are easily investigated and should you be found lying on any account you have given, you can also easily be fired later on.
Don't Be Too Short With Your Answers
Although some of the interviewer's questions can be answered simply by yes or no, it is better that you elaborate. When you talk more your potential employer can better understand what you're thinking and if you're giving the right answers to his questions, he might give you the job as well.
Don't Talk Too Much
In much the same way as I previously stated, you shouldn't talk too much. Show the other person that you are a good listener, not just a talker. One of the worst things that you can do during a job interview is to monopolize it. So keep in mind that although it is best that you talk more, it is also advisable that you don't say more than what's enough.
Don't Crack a Joke
A witty answer is acceptable once in a while but you shouldn't make the job interview into something like a stand up comedy act. When you are serious, the interviewer will think you are serious about the job.
Don't Be Nervous
Don't bite your nails, tap your feet or fingers. All job interviewers are looking for a confident person and if you're too nervous and uncomfortable during the interview, you might as well kiss the job goodbye.
Don't Malign Your Previous Employer
No matter how badly you were treated in your last work, you shouldn't trash your former employer. The interviewer would think of you as someone who bad-mouths everyone and that if you can talk about your former boss that way, you can do it again with them.
