The Exit

 You're the hit of the party, and you've charmed your way into the hearts of all. Now stick the landing.

Read the Room

Is “the Irish goodbye” — i.e., vanishing without a word — ever acceptable?  While you don’t want to make a big interruption, you should acknowledge the departure and thank your host.  There are, of course, always exceptions, and you could follow up after the party to thank the host if the in-person goodbye simply can’t happen. 

What if I Mess Up Terribly?

Say you forget a name, or introduce yourself anew to someone you’ve already met, or spill your drink all over your host’s white carpeting? Admit the predicament, apologize with sincerity and move on.

It doesn’t need to be so scary. There’s the fear of the small mistake ruining everything, but it’s not so likely.