1. Dressing inappropriately.
2. Not taking a phone interview as seriously as an in-person interview.
3. Leaving your cell phone on.
4. Chewing gum.
5. Bringing a cup of coffee or other drink with you.
6. Bringing another person with you to the interview.
7. Wearing sunglasses.
8. Showing up early.
9. Showing up late.
10. Showing up hungover and/or really tired.
11. Going to the interview if you are really sick.
12. Not knowing the interviewer's name.
13. Not introducing yourself.
14. Leaving a Bluetooth earpiece on.
15. Texting during the interviewer.
16. Interrupting the interviewer to take a call.
17. Have background noise (kids, pets, etc.) during a phone interview.
18. Wearing too much much perfume or cologne.
19. Wearing a hat or cap to the interview.
20. Not bringing extra copies of your resume.
21. Not bringing a list of references.
22. Depending on the job, not bringing a portfolio of your work.
23. Playing with your hair.
24. Saying "ummm" or "you know" or "like" too often.
25. Mumbling and using poor grammar.
26. Talking too much.
27. Cutting off the interviewer's question.
28. Not talking enough.
29. Not smiling enough.
30. Telling jokes and laughing too much.
31. Not making eye contact with the interviewer.
32. Criticizing your last company or boss.
33. Not remembering your work history.
34. Checking your notes for an answer to a question.
35. Not following directions if you're given a test.
36. Not being prepared to answer questions.
37. Not paying attention to the questions you're asked.
38. Not taking the time to research the company prior to the interview.
39. Forgetting the name of the company you are interviewing with.
40. Forgetting the names of the companies you've worked for in the past.
41. Not remembering the job you applied for.
42. Telling the interviewer that you really need the job.
43. Telling the interviwer that you need the money.
44. Not knowing enough about the company you are interviewing with.
45. Asking about time off in your first interview.
47. Asking about salary and benefits right away.
48. When asked "Why do you want to work for our company?" providing answers that are focused on you instead of on how you will benefit the company.
49. Not have relevant questions to ask when asked, "What questions do you have?"
50. Neglecting to thank the interviewer for the opportunity to meet with him or her.
Not sending a thank you note after the interviewer.