Bring a Condom

First of all, anyone who is having recreational sex should be wearing protection, whether you've been together for five years or five minutes.

But I use birth control!
Nice try, Lazy Susan. Birth control fails all the time, so if you want to be 99.9% sure you won't get pregnant, use a condom.

He says he doesn't like to wear condoms.
If he's pressuring you into doing something you're uncomfortable with, you probably shouldn't have sex with him at all.

He says he's clean.
Are you going to put your life on the line for a few minutes of unprotected bliss? Some STDs take months to rear their ugly head, so unless he's been celibate for the last year and tested every month, I recommend you wrap it. He could also be lying, so don't discount that option.

We're safe- he pulls out!
Don't even get me started...

I'm not planning to have sex tonight.
Yeah, but you never know. When you're in a compromised state, it's easy to start bargaining with yourself about what you're willing to do. A steamy makeout session could go down that road, so it's better to be safe than sorry.

Even if you don't need it, someone else might. I've been in plenty of situations where my friends are about to seal the deal, and realize they're unprepared. They will be forever grateful to you for your help. Also, do this enough times, and you may earn the coveted title of "Cock Assist," reserved for only the coolest of bitches.