Something on the ankle or foot could be nice-- you could show it off with a great pair of shoes, but cover it with a sock just as easily. :) This could be a bit trickier, but I also like the idea of putting it behind your ear, so you could style your hair depending on how visible you want it to be on any given day.
Beat of luck with the tattoo! Just out of curiosity, what sort of design are you thinking of?
...What does being a psych major have to do with getting a tattoo? Just curious.
I think tattoos that are meaningful, well done, and not huge are good looking. For girls I like the following places: inner wrist, foot, behind the ear, back of the neck, hip, and upper arm (if you're going for a larger one).