Make a Positive First Impression
Impressions are typically formed in the first 60 seconds!
Things that contribute to a good first impression: firm handshake, eye contact and a confident voice. For example, "Hello, Professor (or Dr.) XX, I'm pleased to meet you. I'm Lucy XXX and I'm here for the WISP internship interview."
In some cultures and some families, these assertive behaviors are not encouraged, especially when there is a status difference between the two people (and you are the one with the lower status). You may feel a bit out of your comfort zone if you have not done this before. Practice beforehand with your roommate or friends so that you feel more at ease.
Your presentation has a bearing on a mentor wanting to work with you — promptness, courtesy, appropriate dress, and whether you are engaged (actively participating) in the interview.