This article is from the Stand-up Comedy FAQ, by Steven Rosenthal and Steve Silberberg (email@example.com) with numerous contributions by others.
A. Find a bar or coffeeshop that has a small performance area that's
separate from the main bar area.
Make sure you can perform without worrying about the juke box, the
television set or waiters carrying food.
Ask the owner for permission to have small open mikes there during a time
when it's slow anyway.
Send notices to your local newspapers and drama classes to advertise that
Open mikes that mix music, poetry, etc. with comedy tend to be more fun for
the audience members than those that just feature bad, open-mike-level
Make sure that the bar owner understands that most of the performers will
be really, really bad.
Try not to locate the acts any place where the performers will frighten
away the paying customers.
Charge a fee and give the some money to the bar owner.
Avoid setting up your open mike at a family restaurant or anywhere else
where many kids are present.
If you do end up somewhere need food or kids, make it clear to the
performers what the limits are.
Yes, censorship is bad, but there is nothing worse than a bad comic doing
stupid enema jokes while people are eating. Especially when it's the same
bad enema jokes you've hard 50 times before.