Another problem you may run into in dealing with the audience, especially if alcohol is being served during the performance, is hecklers.
Some of them actually think they're helping you with their, they believe, funny remarks. Often simply ignoring them will do the trick; they'll take the hint and shut up. Sometimes, though, they'll be more persistent, in which case you may have to shut them down with a topping remark, glaring them down with an icy, "You know, sir, there can be more than one murder this evening."
Be warned, however, that they may have a comeback -- an invitation to verbal combat that you MUST win in order to retain the audience's respect and control. If you're not up to it, better leave the put-down to another cast member who is, or have a staff member of the establishment quietly ask them to hold it down or get out.
On rare occasion you may run into an abusive drunk who is clearly out of control and ready to complain about everything and everybody -- usually at the top of his lungs. Arguing with someone this far gone is useless and holds up the show -- they must be removed for the good of everyone else in the audience so that the performance may continue.
Controlling an audience is never simple, and can only be learned through painful experience. Experience in stand-up comedy is a great training ground, but the easiest way to keep the show rolling is to be consistently entertaining. If everyone's having a good time the show can become like one big party, and you won't have to worry about audience control -- they'll already be in the palm of your hand.
Next Step: Dinner Time.