first time

My girlfriend and I (16/18 respectively) are planning on having sex soon. And I really want it to be special with her since it is her first time. We can't do it at my house due to an extended family. Also, I don't want it to be in a hotel room or anything. Any suggestions as to where and how i could make it memorable for her and not just like "oh we just did it"? (: and I'm sorry, I've been a lurker on here for a while, this is my first post so if I posted wrong. I'm sorry! Haha!