I agree with
@Windsong and
@Kaga-kun.
Maybe waiting until you graduate is the best decision. It gives you more than enough time to plan out just exactly what you want.
I mean, it kinda says something if you already didn't have an idea and were asking us to pick one for you, don't you think?
Personally, I've been thinking about getting tattoos since I was like, in 7th grade. And it's given me more than enough time to pick at least three ideas and three body parts to go with. I want a Mayan tattoo on my right pectoral, the head of an Aztec Eagle warrior on my left, and something with the grim reaper on my right forearm.
And those aren't just cuz I think they're cool. The ones that'll go on my pectorals are part of my heritage. I come from Mexican and Guatemalan decent, and they both come from Aztec and Mayan blood respectively. As for the reaper, I've always been fascinated with the idea of death, and my uncle on me dad's side (who shares my name) has one that I've always thought was cool. I don't see him much anymore, and that's more of a sentimental thing.
But even though I have these ideas, I'm not going to rush into getting them. Like windsong said, I'm going to have to find an artist who'll be able to do the designs I want well. On top of that, there's no way I'm settling for any shop/tools/etc that are any less than perfect. Having a tattoo is cool, but having Hepatitis or some other disease isn't.
Hopefully you haven't gotten one already, and you decided to at least wait and think about this a little further before making hasty decisions and ending up with something you'll hate in the long run.