Even if you are given short notice – or no notice at all – you should have the facts and other information you need at your fingertips.
Express your opinions and explain your cause with enthusiasm. If you aren’t excited about it, why should anyone else be?
Vague answers suggest that you are hedging or that you can’t back up your arguments. Specifics are more convincing.
Examples and narratives help to dramatize a point so the audience will remember it. Using anecdotes also makes a response more conversational.
All the preparation, enthusiasm, specifics, and anecdotes are useless if they’re wrong, or if a speaker gets them mixed up or hopes no one will notice departures from truth.