The process involves two staff members to the research group you are interested in working with. They typically begin by explaining the project that you will be working on and using your resume as the basis to understand if you are a good fit. They want you to explain in detail how your experience will be used for the purpose of the project.

Simple behavioral questions. Just contact your favorite professor and ask. Most of the time they need the help. Most of the time it will not be paid, but the experience is worth it.