Being roasted is an honor, but you must be careful to honor people while you are roasting them during a public speaking engagement. Joke about things that are obviously untrue, then exaggerate them to make them more obvious. Or, you can outrageously exaggerate things that are true.
When choosing the butt of a roast joke or story, pick big targets. Never make fun of a small target (janitor, secretary, etc.). Make fun of the boss. He or she is still the boss after all the teasing and will look like a great sport for going along with it.
Members of 'in' groups can joke about their peers and insult each other all they want. Bob Hope made fun of Ronald Reagan. Everyone knew they were buddies.
If you widely spread an insult or collection of insults, the group can laugh together. No one is individually embarrassed. The same remarks aimed at an individual removed from the cohesive influence of the group might cause someone to get upset.
Always clear your comments IN ADVANCE! Unless you are participating in a full-blown roast program, always make fun of yourself first. If you kid yourself first, the audience will be more receptive when you kid them. Here are some roast examples:
To an AT&T executive:
If a Martian called Ed's office to contact earth, he'd try to sell them on the benefits of our new 800 service.
Keep remarks focused on unimportant things that can't be damaging!
Folks we are here tonight to Roast Joe. I'm particularly happy to be here because I can now say in public all the things I've been saying behind his back. He/she is a man/woman of the world . . . and you know what bad shape the world is in.
Insult about areas of recognized strength and superiority!
To a great family man and/or community leader:
Joe's (neighbors/business associates/preacher, etc.,) all say what a wonderful couple he and his wife make . . . if it wasn't for Joe.
To a well-known philanthropist:
He is a man of rare gifts . . . he hasn't given any in years.
At a program with a long head table with lots of speakers, an emcee might say:
The emcee's job is not to be wise or witty. In fact, it is his job to appear dull so that the speakers on the program will shine in comparison. Tonight it looks like I'm going to have to rise to new heights of boredom.
To the audience the emcee or speaker might say:
I'm glad to be here tonight to look into your faces. . . . And God knows there are some faces here that need looking into.