The first two commandments of moderating are here, the third here, and the fourth here. I started out without much concern on the order of these pieces of advice, but the list seems to be developing a structure: The first two commandments are the most basic. They’ve been followed by three on formulating questions. After that, we’ll have a couple on preparation and directing traffic, followed by the most important commandment of all. Now for the last piece of advice on questions:
5. Paint Pictures — I’ve touched on this in Nos. 3 and 4, when I suggested how scenarios or hypothetical questions can be used to ask a hard question or get panelists talking to each other. But the principle is applicable in many other contexts as well, and merits its own commandment: Whenever possible, look for opportunities to paint a picture — set a scene — that you then ask one or more panelists to fill in. A couple examples:
Compare these two questions:
A. “What do you think is the most important step public schools can take today to improve their students’ education?”
B. “You’ve just been appointed Principal of P.S. 11, a public middle school in Brooklyn where two-thirds of the students are unable to meet the English or math standards for their grade. What is your first step as principal? Walk us through it.”
Or, compare these two questions:
A. “What sort of pitfalls should one watch out for in marketing a new product?”
B. “Think back to one of those moments of realization — the moment you realized that a big, ambitious marketing push for a new product had just fallen flat on its face. What was it, and what went wrong?”
Asking questions that paint pictures — or that call up a picture in your panelists’ minds — pulls out more specific responses, triggers memories, encourages storytelling. It helps your audience see the world through your panelists’ eyes — which is probably why they came to the discussion in the first place.
A Few Good Questions 
My students are preparing a panel discussion on self esteem. what are some good questions and preparation steps recommended?
In addition to reading material on the subject, you could have each student to ask family, friends and classmates for examples of dilemmas they faced concerning self esteem. The examples could involve one’s own feelings of self-confidence (“I was afraid to speak in front of the class”; “That other kid’s teasing made me miserable even though I knew I shouldn’t care what he said”), or it could be about promoting someone else’s self-esteem (“My little brother says he ‘feels like an idiot’ because he’s dyslexic. How can I help him?”) The dilemmas could be reported with the names changed or removed, and several could be chosen to serve as scenarios to challenge the panelists.