Do not arrive late: Prepare yourself for circumstances that may be out of your control, like a traffic jam, so try and leave a bit early. If you see that you are running late, call 20 minutes prior to your interview time and let your interviewer know the situation.
Dress for success: It doesn’t matter if the job descriptions say it’s a business casual environment; wear a suit to your interview. Make sure you look clean and neat.
Don’t be cocky: Confidence is good, but cockiness is a turnoff, thinking that you are better than your interviewer will show, and it will worsen the situation. On the other side of the coin, don’t be too insecure either. Be confident in your knowledge about getting the job done without overstepping boundaries.
Bring a resume with you: Even if they have one, it is always good to have one to three handy, as if the interview may go very well and you may meet with more than one person. Also make sure that your resume is error-free. And please do not pull out your resume from your bra!
Don’t talk about your other business: If you have a construction company or worse if you have a website that gives Playboy look meek on the side but you are interviewing with an Oil & Gas company do not bring it up. It shows you are not interested in the position and the company and it is unprofessional.
Don’t badmouth your past employers: If you do this, your potential new employer may question what you may say about them; it doesn’t matter how well or bad terms you left.
Have a positive attitude: This shows excitement and interest in the position. If you have a bad attitude, the interviewer is going to think that you may be even worse if you get the job and bring everyone down. When it comes down to the interviewer may go with the person that had a better attitude even if their skills weren’t as good.
Have Manners: Always be polite, say thank you, please and excuse me and don’t burp in the interview or chew gum, it is plain rude.
Do your homework: Research the company and have at least one to three questions. Questions show interested in the company.
Do not ask the interviewer out: this will not get you the job and it is inappropriate.