Me and my girlfriend are supposed to have sex this weekend..

I've been with my girlfriend for 14 months. I'm 20 she's 23 and we're supposed to have sex this weekend but I have no idea what to do. My mom was catholic and I spent all my years on a catholic school(that was fucking hell!) Sex ed was pretty must abstinence class so I really know nothing about sex at all. She knows a virgin but I don't think she knows how clueless I am. I'm scared I won't be as good as anyone else shes been with... How do I make her happy.... How can I be a good lover and make her feel good. Idk if I want her to do anything to me because I don't want to release too soon.. I really want to be good for her..