If you are serious about landing a job or internship, follow the three "P's" of job interviewing in order to maximize your chances of receiving an offer. They are Preparation, Performance/Practice, and the Post-morthem (follow-up). If you get anxious before interviews, following the four P's will go a long way to helpl you control the butterflies so that you can be yourself and show the employer all the valuable qualifications you possess.
Preparation - This is the research stage: know yourself (your career interests, why you like the employer, why you want the job, and your resume backwards and forwards); know the field or industry (via online and print resources); know the organization (their web site!); and know the position (consider carefully the job description and discuss it with a Career Center counselor). Attend a Career Center Interviewing workshop!
Performance/Practice - This stage is covered in the linked sections listed below, during the Career Center's Interviewing Workshop and with a counselor during a Mock Interview. You can also discuss all aspects of interviewing with a counselor in a full-length appointment or during drop-in hours. Briefly, good interview "performance" (behavior) includes clear verbal communication (speak at an even pace; do not ramble or give too much detail), positive non-verbal communication (maintain confident eye contact and body posture), demonstrated interest in the job (expressed both in words and facial expression), excellent listening skills, and engaged interaction throughout the interview, including questions at the end of the meeting.
After you do the research and learn about effective interview behavior, develop your interview skills by reviewing sample interview questions and practicing the answers aloud with yourself or a friend. You must schedule a Mock Interview with the Career Center! A Mock Interview is an invaluable form of practice!
Post-mortem (the follow-up) - This is the thank you letter, which can be sent either by email or snail mail. See a sample in the Resume & Letter Formats section.