1. Trying to read into every word or action from your interviewer.
2. Stressing out over elements of your job applications that really don't matter.
3. Scrimping on the cover letter.
4. Thinking that you have the job before you have an offer.
5. Not explaining why you'd excel at the job.
6. Taking advice from people with no experience hiring.
7. Taking it personally.
8. Forgetting to evaluate potential employers just as much as they're evaluating you.
8 Errors You Must Stop Making in Your Job Search - On Careers (usnews.com):