7. You're not asking to be hired
You aren't at this interview to make friends. You are here to get the job. Make sure when you leave that interview room your interviewer knows that you want the position, without any semblance of doubt. Go right out and say it. Interviewers are looking for ambitious, motivated candidates. You have nothing to lose, kid.
8. You're lying to yourself When you put on a facade during an interview, you've already lost the battle. Chances are, the person interviewing you has done this before—probably many times, and they'll see right through your overblown attempt at fitting into the culture of the company. If you aren't a good fit, you aren't a good fit. This will shine through eventually and it's better now, rather than a month into the job after you've relocated to Portland.
9. You smell Smell is the sense most associated with memory (I still remember my first mid-summer trip to Chinatown like it was yesterday). So when that HR rep thinks back on your interview and only remembers the mustard/General Tso/Pop-Tart olfactory combo on your breath, she’ll be feeling unsettled (for more than one reason). Get some Tic Tacs, gum, or simply scour the landscape for some wild Myrrh saplings; but 7-11 is probably closer, unless you live in the New Testament.