Not sure where I found this (it is not original) but I wanted to share with as many students will soon be undergoing the interview process.
1. Arriving late.
2. Arriving too early.
3. Lighting up a cigarette, or smelling like a cigarette.
4. Bad-mouthing your last boss.
5. Lying about your skills/experience/knowledge.
6. Wearing the wrong (for this workplace!) clothes.
7. Forgetting the name of the person you're interviewing with.
8. Wearing a ton of perfume or aftershave.
9. Wearing sunglasses.
10. Wearing a Bluetooth earpiece.
11. Failing to research the employer in advance.
12. Failing to demonstrate enthusiasm.
13. Inquiring about benefits too soon.
14. Talking about salary requirements too soon.
15. Being unable to explain how your strengths and abilities apply to the job in question.
16. Failing to make a strong case for why you are the best person for this job.
17. Forgetting to bring a copy of your resume and/or portfolio.
18. Failing to remember what you wrote on your own resume.
19. Asking too many questions.
20. Asking no questions at all.
21. Being unprepared to answer the standard questions.
22. Failing to listen carefully to what the interviewer is saying.
23. Talking more than half the time.
24. Interrupting your interviewer.
25. Neglecting to match the communication style of your interviewer.
28. Bringing along a friend, or your mother.
29. Chewing gum, tobacco, your pen, your hair.
30. Laughing, giggling, whistling, humming, lip-smacking.
31. Saying "you know," "like," "I guess," and "um."
32. Name-dropping or bragging or sounding like a know-it-all.
33. Asking to use the bathroom.
34. Being falsely or exaggeratedly modest.
35. Shaking hands too weakly, or too firmly.
36. Failing to make eye contact (or making continuous eye contact).
37. Taking a seat before your interviewer does.
38. Becoming angry or defensive.
39. Complaining that you were kept waiting.
40. Complaining about anything!
41. Speaking rudely to the receptionist.
42. Letting your nervousness show.
43. Overexplaining why you lost your last job.
44. Being too familiar and jokey.
45. Sounding desperate.
46. Checking the time.
48. Sounding rehearsed.
49. Leaving your cell phone on.
50. Failing to ask for the job.