Collect. Analyze. And repeat. A research internship is a great way to gain experience in the career you're heading into. It provides you with a lot of information related to that field and presents problems and real-life situations that you may have to deal with during your career.
The research internship is also a great way to impress any potential employers you might have. Plus, you'll see how the career you've been dreaming of really is day-to-day. You may even find out it's too boring for you. But you'll probably end up loving it, even more than before your research internship.
Typically, research interships are saved for students who are on their last year of school or those who recently graduated. Most internships are paid, so you won't be doing all of this work for nothing.