Well there other things to do but it depends on your age. Don't want to let you have you say it for everyone to know, but if you can drive then maybe take her out to a nice romantic dinner and then go back to your place and watch a movie that she likes...
Hey! Did you find an idea in the end?
As a woman, of course I find roses and every other clich้ very sweet when they come from the loved one! but really, maybe Im easily happy but anything is sweet..
Also, it really depends on your budget and age. and where you live.. I find that arranging things that seem "impossible" is very sweet.. such as telling her you love her in two different states at the same time, if you live near a border.. or name a star after her! I dunno... really its all about imagining something and make it happen...
My advice though is, look at her, and tell her you love her... on Valentines day, and every other day!
Also is it really about expecting something back? Im sure she will get you something, but you have to focus on what you wanna do for her, no matter what x
hope you have good time with her x