Dressing up a bit never hurts, but be sure to look neat. Avoid wearing shorts or sandals in a biochemical lab, as this is generally unsafe clothing in the lab. Remember to bring a copy of your resume, if you have prepared one. Be enthusiastic and interested. Few researchers dislike talking about their research, so be prepared for a sometimes lengthy explanations of the research in the lab. Leave enough time so that you are not rushing the meeting. Ask questions, since the business of science is asking questions. This is a great way to show your interest and to engage in the conversation rather than only listening passively to the professor’s explanation. Asking a good question is often more impressive on a professor than any achievement you present.