1) Come to your interview prepared.
This means having reviewed the hiring company's website, searching for news articles and blog posts about them, reaching out to anyone in your network with a connection, etc. Do anything and everything you can do to show that you really want this job.
Just showing up to the interview isn't enough. Even though it is a bit hokey, using a phrase like "I noticed on your website..." lets the interviewer know you did your research. If you're interviewing with a medium or large sized business that is likely to have been in the news, a well known blog, or a magazine then reference that as well. "I saw in the WSJ that you all are expanding into the Asian market, blah blah blah."
2) Remember that we want to hire you.
This may surprise you, but it's true. Whomever is interviewing you would probably rather be doing something else (and sometimes this shows...), and would like nothing more than for YOU to be the perfect fit for the job.
So relax. Know that you are prepared (and be prepared). Bring at least 3 copies of your resume in case. Sure, we should do our job and have a copy with us, but it shows that you care, and these subtle little hints have a profound impact on how the interviewer perceives you.
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