First time having sex

I'm going to have sex for the first time on Wednesday night. I'm 24 and will be with a guy that I've been seeing for over 5 months - he's older and more experienced. We will be using a condom, but should I be using anything else as an extra precaution? It's obviously not enough time to go on the pill or have anything more evasive but was wondering if there are steps that I should be taking.