1 Cancel, don't show up, or leave early. People invite guests out in a spirit of misguided enthusiasm and then regret it horribly.
2 Keep to your room. The old Victorian principle of child-rearing applies to guests as well: They should be neither seen nor heard.
3 If you must leave your room, laugh raucously at everything your host says. Compliment him on his skin tone and lack of varicose veins. And don't mention his alcohol intake, flatulence, or lack of personal style.
4 Ignore household vermin and don't comment on the ticks in the backyard.
5 Give your host a huge gift certificate to Barneys.
Simon Doonan is creative director of Barneys.