Learning about the background of the audience is important because, as two-time world heavyweight boxing champion George Foreman told a 2007 Forbes.com panel on public speaking, the speech is not about the speaker. Rather, it is about helping and motivating others. A powerful speech does not have to be long. President Abraham Lincoln's powerful tribute to the dead at Gettysburg was only three to four minutes long.
A powerful speech starts out by identifying with a problem and then shows the path to resolving it. Nick Morgan, founder of the speaking consultancy firm Public Words, suggests structuring a speech into "three acts" held together by one or more stories. The first act, which is the introduction, must get the audience's attention. For example, a business executive might start by lying out the problems facing the company, while a public official running for office might start with an observation connected to his theme for the day.
The second act, which is the body of the speech, establishes the need for action. Images more than words make a speech powerful, counsels Harvard University lecturer Steven D. Cohen. He points to then-Sen. Barack Obama's use of powerful images at the 2004 Democratic National Convention, such as "The hope of a skinny kid with a funny name who believes that America has a place for him, too." Repetitions can reinforce key messages. For example, the Guardian newspaper's Mary Beard points to Obama's use of the "Yes, we can" phrase as a rallying cry for his presidential campaign.
The third act is the conclusion. Ask the audience to act. For example, King asks the assembled masses at the Lincoln Memorial to "dream" of a future where someone like an Obama might become president one day.
Even the most well-constructed speech falls flat if it does not connect with the audience. Public speaking organization Toastmasters International advises speakers to "create a bond" with listeners by making eye contact for five to 10 seconds. Gestures should be convincing and movements on stage should be purposeful. Persuasive speeches are about passion: the voice, gestures, eyes and the words must work together in perfect harmony to create an enduring connection with the audience. It takes practice to master all the technical elements because public speaking is a learned skill, suggests Cohen, not a gift.
Speeches become powerful when they are in sync with the speaker's actions. For example, a corporate executive who speaks about cost controls and then spends thousands on a luxury retreat will lose the respect of her employees. A political leader cannot properly inspire voters if he does not live a life of integrity.