Providing that its not too cold, you should grab a blanket and go to a park, lay down and watch the stars.
Or go to the beach if there is one around you or to a fountain and do the same. Buy flowers, or just buy her something cute to surprise her with, something to hide in your pocket. Whether it's a little book from barnes and noble (they have little teeny-tiny ones on the subject of love and dating for like $5-$10), or a small box of Godiva chocolates (you can also pick this up at Barnes and Noble). And wait until you guys are sitting down star-gazing and having a cute conversation to give it to her. Also, make sure and compliment her tons and tons, always smile, maintain constant eye contact, tell her how excited you are, how happy you are... sweet cute things like that. Even if you guys just end up going to a beautiful park where there's benches and something sweet to look at (the city lights, trees, whatever), you can make it romantic if you try. And you should. I wish you the best of luck!
Irena (S13Grl)