I'm still a student, and I:
1) Have been lucky enough to get a scholarship through my schooling and do not have student loans.
2) I currently live in a city without the need for a car (and actually, having one would be inconvenient for me personally, since parking is hard).
3) Do have a couple credit cards, with long history and (I think high) maximums. I don't need any more credit cards.
My credit score is steady ~765, but it has been there for a long time. Is there anything I can do to raise it without taking on unnecessary loans to pay them off?