By the time you get to an interview, you've already made a good impression with your networking, résumé, cover letter, LinkedIn page, and so on; otherwise you would never have made it this far. Your task now is to seal the deal, and a good performance in the interview will go a long way towards doing that.
Fisher stresses building rapport with the interviewer, which means making the interviewer feel comfortable with you. He recommends letting the interviewer initiate the handshake, for example. and watching how the interviewer sits and stands and modeling your behavior on the interviewer. Read the post for details and examples.
There's an exception to Fisher's "let the interviewer lead" principle: The interviewee should always be prepared to initiate eye contact, Fisher says. Looking the interviewer in the eye at the beginning of the interview is vital. "Avoiding the other person's eyes sends out the wrong signals and can give the impression of 'shiftiness', dishonesty, having something to hide, or lacking in confidence," Fisher says.
Don't worry about acting cool, whatever that means, Fisher advises. Act like the person they want to hire. You can go back to being cool once you're on the job.