try this:
Call her up and tell her that you guys are going to go somewhere but dont tell her where, tell her its a surprise
Then, when you get up to the door give her to grab something warm, cuz WERE GONNA GO SOMEWHERE!
Then have a boat prepared with two fishing rods, and say you guys are going to go fishing, then when you get there, pretend youre fishing and say, whats this other rod for? then reel it up to reveal two glasses and a bottle of sparkling cider. then talk and stuff and then have some hot sex in the boat. or not. just talk and stuff and pull out some food or something, i dont know what kind of food would be good, but bring something, and then row back then walk her home, then give a nice big hug, the go up to her room.... BWAHAHAHAHAHAHAHA!!!