I approached a principal investigator directly, via email, asking about available positions. First I had a phone interview then a second interview in person. During the first interview, the PI asked about my goals and a time frame for the internship. He also briefly want over skills and experience listed in my resume. The second interview had more in-depth questions about my skills and experience. Then he explained the project I would help with before I was taken on a tour of the labs and introduced to other researchers.

Very easy process. Typical questions such as behavioral questions and talking through previous experiences. The entire process was short, starting with a screening interview and then a brief conference call with multiple team members.