What's the best way to approach girls at a cafeteria or eating place in the first week of college?

Hi, so college is coming up and I always enjoy meeting new people. I figure the first week of campus I can meet people in the cafeteria. People should also probably be more approachable I would guess.

If I'm approaching someone to sit down with them at a cafeteria table, what's the most polite way to ask someone if I can sit with them and talk with them.