My ex used to do it this way: (insert description here).

Bringing up past sexual partners is a sure-fire way to insecurity. Don't make your current bedmate feel like he's not good enough, otherwise you're the one who will feel the consequences. If he doesn't feel sexy, he can't give you the sexy. Got it?{relatedarticles}

If there's something you want him to do, take command and show him, but don't bring up exes or old flames; you're only going to make him jealous and turned off.

The wrong name.

This one's bad. There's no quicker way to end a romp than by calling someone by the wrong name. If you're unsure of your partner's name - don't attempt to say it at all. If you somehow get it right, you're in the clear; however, if you get it wrong (which is pretty likely) you're in the doghouse. It's disrespectful, rude, and shows them you were really just in it for the sex all along. If you're questioning their name in any way: don't say it. And definitely don't guess.

Don't tell my boyfriend.

When a guy hears this, it's a huge cue to slam on the brakes. One, they're violating man code: they shouldn't be with someone else's girl. Two, what if the boyfriend is bigger than him? What if he's a real tough guy with anger issues?