I need every interview tip that you have

Dress well, but don't go for anything to out there, just a nice suit, shirt and tie.
Keep eye contact.
Don't give one word answers, expand on everything.
Ask some questions.
Arrive 10 minutes early, DO NOT be late.
Shake hands upon arrival and departure. Make the hand shake firm but don't crush their hand.

Act like a professional.

In all reality, there are only a handful of staples that you should always do. You are interviewing with another human being, not some mechanical entity that always likes the same type of person, which a lot of people seem to believe.

Other than what has already been mentioned, be qualified or know someone. Those are about the 2 most important things in this job market.

Show them your pen0r.

Be friendly and make sure to smile. Sounds obvious, but many interviewees come off as standoffish and churchmouse-ish. If you can manage respectful conviviality, you'll be ahead of the pack.

Be prepared to give a beyond boilerplate response to the question "Why do you want to work here?"

Relatedly, prepare questions that show that you have done your homework on the company.

Don't be afraid to try to establish a personal connection with the interviewer if you two have a genuine interest in common.

Try to turn it into a conversation with the interviewer about how you fit the role. I try to paint a picture with my answers about how my background, skills and ambition fit their industry and company, and economic times.

answer questions in 2-3 stages

what was the situation
what did you do about it
what was the result

keep answers between 45 seconds and a minute and a half

take time to think about the question before answering, and if you need it repeated ask

ask intelligent questions about the job, and company, know a little bit of history, but don't throw out random facts as often times it comes across nowhere near how you wated it to.

what industry and what kind of job?

Rehearse the answers to questions you expect to be asked. That will help prevent it.

I had an interview yesterday, got asked all of these (which I thought were quite tough for a job that is a direct demotion from my current role!): Tell us about a situation where you worked with a difficult individual and how you resolved that situation Tell us about a mistake you made and what you did to put that mistake right Tell us about a time where you worked in a team to achieve a goal Tell us about a time where you acted above your level of responsibility in a work situation Tell us about a time where you had to resolve a situation involving the use of sensitive information Having answers prepared for those should avoid any nasty surprises. And like Robbie says answer in the 2 or 3 stages making sure you give the outcome of your actions. Also, at the end when they ask if you have any questions, ask if there's anything they would like you to go into more detail on. I've had feedback saying I didn't get a job because I didn't talk enough about my menial office experience which I took for granted, but they needed me to actually say I knew how to do filing in the interview to tick the office skills box. If the interview panel is fair they will ask the same questions to all the candidates. If you ask them if there is anything more they want to know this lets them put any questions they may have wanted to ask you specifically, but were constrained from asking in the formal part of the interview due to keeping impartiality between candidates.

Be classy, wear a tux.

Brush your teeth. Smile.