Drink plenty of water, and breathe deeply, though not at the same time.
Practice good posture, or wear clothes that distract the eye from your bulges.
Eat fruit rich in Vitamin C as it may be the only chance you get to pucker up today.
Be as grounded as a 3-legged samovar and and keep your spout drip-free and clean.
Put your best foot forward and dance like no one's watching because they're probably too embarrassed to look anyway. Either that or they're too busy texting, twittering, e-mailing, or blogging and aren't paying attention to you in any event.
I don't know about you, but I'm feeling better already!