Losing my virginity !

Im an 18 year old female and have a boyfriend of 3 months and I know that I want to lose my virginity to him. He knows I'm a virgin and respects any descision I want to make with it. We've done other things before like given each other head and he's fingered me. What sort of things should I know about becoming sexually active for the first time? I know it might feel uncomfortable and to take precautions with safety but is there anything else I should take into account and things I should start doing once I become sexually active?