10. You're talking a lot, but not saying enough
Does that sound stupid? Well so do you when you end up telling your interviewer that story about your dog eating some woman’s pizza in Toronto. Be friendly and communicative, but don’t ramble on like your crazy uncle Harris. Your message will be drowned out in all that chatter. Keep it tight, concise, and pertinent.
11. You're lying about your resume
Exaggerating in your interview is pretty much expected. Out-and-out fabrications are not. You know a little Spanish? Great, say that. You once saved a company from going bankrupt by mediating a high-stakes buyout? This is for an entry-level position. Dial it back.
12. You're fudging-up your follow-up
A concise "thank you" the day after your interview is all that's needed. Reiterate your strengths, why'd you be a good fit at the company, and make sure to keep up the enthusiasm. If you don't hear back for a week or so, send another quick follow-up, asking if there is any news. Like I said, while you are interviewing, you basically have nothing to lose. Just don't spam your prospective company's inbox like the son of a Nigerian prince.