Can you please give me advice? I'm sorry i wrote alot and it's a mess but IDK what to do!?

This weeknd i'm goin to a dance party with my gf in this girl's garage. ive done everything but and from what ive heard the case is the same with her. but with people in relationships, shes no dirty ho. we've done out fair share of hooking up and stuff, nd we hav some pretty deep feelings fo eachother. i want some advice on how i can hint to her tht we should go somewhere private. should i just ask her? "hey, u wanna go somewhere with a little bit more privacy?" sometin alone those lines?? i kno tht while we r dancin we'll just hook up there in the dark dance but i wanna be alone wit her. can you give me some advice on how to either send her some hints besides what i already said, and/or turn her on a bit so she wants to go wit out me havin to like instigate the whole thing?? im talk bout probably oral at the most and itd be in a treehouse if we did leave for privacy we r almost 17. dnt preach to me bout underage n **** idgaf, and anything you say will not make a difference.