For my gf bday last year we started out on a picnic had the normal picnic food and we had a cake that I made her after that we went to the wisconsin dells which is a big tourist spot about 20 min from where I live. We went horseback riding and then went to a hotel that I got for the night. Surprised her with flower pedals on the bed and a big single rose in a vase and a card. Left the room and went to a nice restaurant to eat. Came back and went swimming in the pool at the hotel. Went back to the room hung out in the jacuzzi with the lights out and candles all around and romantic music playing. The rest you can leave up to your imagination. So basiclly all I did was give her a day to remember. Hope it gave you some ideas. If not pm me I got some others.