"When people come in, everybody gets a little bag of goodies, a 'perform-along fun pack,'" Ball explains. "It has some props, shall we say.
"What I do is I make sure everybody knows how everything is going to work. (Audience members) are allowed and encouraged to cheer for the good guys and boo the bad guys, and sing along. I go through the goodies bag with them, so they know, for instance, when Glinda comes along to get out the bottle of bubbles, and when Tin Man gets rusty, they use the ratchet noisemaker. And I warm them up for singing and run the costume parade."
"Sing-A-Long Wizard of Oz" has been on the road since June, and Ball, a Chicago resident, joined the tour in July.
"In July, they did three weeks on Broadway, and after New York, there was one performance at the Hollywood Bowl," he notes. "There were 16,000 people there - 2,500 in costume."
Ball says he's enjoying the emcee stint for a variety of reasons.
"It's a good time for everybody," he explains. "Different people see this show in different ways. The kids - to them, it's just an incredible movie, and it is - it's an incredible movie. ... For adults, there's all kinds of nostalgia wrapped up in the movie, whether they're remembering watching it as kids or watching their kids watching it.
"And the solo adults - it's fun dress up for them. They sing aloud and shout and do all things that you don't do as an adult."
The show has its challenges, but maintaining its novelty isn't one of them.
"The first thing that isn't a challenge that most people ask me about is it's not a challenge to keep it fresh," Ball says. "You've got a really, really live audience, an excited audience, people who have been waiting months to be there that night.
"The challenge for me, as an actor, is reading my audience. Even though everybody sees it differently, each audience has an aggregate personality. Some audiences are mostly kids, some mostly adults, and different audiences have different personalities. If I'm doing my job well, I can read that personality, have a good sense of the personality and sort of play around a little with it. With my introduction, it's not entirely a canned thing. I try to play with the crowd, and play in a way that works forthem. That's the challenge for me."
Ball knew early on what sort of career he would pursue.
"I'm one of those sort of stereotypical stories," he explains. "I was acting at summer camp when I was 5, and I never got smart enough to get out. I went to college to study acting, and I've been doing it professionally for 20 years, altogether for 34 years."
In that time, he's played a number of roles he's really enjoyed. "The one before this (current one as emcee) is a favorite - I was John Adams in the musical '1776,'" Ball says. "That was just a wonderful show, and a wonderful role.
"Oh, let's see, George in 'Of Mice and Men,' Laertes in 'Hamlet," and - this one's kind of obscure - Eddie the Bartender in 'Conversations With My Father.' And I liked Che in 'Evita.' I did that one twice - they've both been a long time ago. Oh, and my next one."
Your next role? Which would be ...?
"I have no idea."
Ah. Anything else?
"I'd like children and puppies and I'd like to work for world peace."