Take it seriously. Going into your position with a determined attitude will show your new employer that you want to help improve their company. Someone who acts like they want to be at work will be much more memorable.
Network. Go out of your way to communicate and connect with other interns and full-time employees at the company. Even if you don’t end up wanting to pursue the organization after your internship, you’ll have made some great connections that could open doors in the future.
Become a sponge. Whatever sort of company you’re working for, learn as much as you possibly can. Even if you’re not insanely interested, the knowledge you can gain from the people around you will be invaluable to you later on. Listen carefully and ask a ton of questions.
Get feedback. Use those around you to check how you’re progressing. This will show that you care about how you’re growing and serving the organization.
Have fun. You’ll only have a couple chances to do internships when you’re in college. Make friends and take every opportunity that comes your way!