You used all your best tricks to get him in the first place - you dressed to the nines, you flirted, you used all your charms and you behaved in a way designed to get his attention and drive him wild. And you did a great job! But that's when it's time to stop it.
Even if you're naturally the most flirty person in the world, and it's just how you speak to people, no man wants to see his woman flirting with other people - especially not his own friends. Be mindful that how you behave when you're single and how you behave in a relationship are two different things, and you can't carry on swapping cheeky texts and conversations with guys you used to speak to. Also, don't embarrass him needlessly in front of other people if he's done something wrong; if it can wait until you get home, then wait until you get home and have it out with him there.