Make temporal comparisons

Repetition can be very effective.

Use short, pithy quotes. Clever people over the years have created witty aphorisms, so you should borrow them when it is appropriate.

Try humour - not by telling a story or a joke as such, but by using a short, witticism. A little humour in the opening sentences of a speech relaxes the audience and positions them onside with the speaker. Humour in the last sentence or two of a speech leaves the audience with a warm feeling towards the speaker.

Sometimes you can use the same word but in a different context.

One way of commanding attention is to use a redundant, but attention-seeking, short sentence. Tony Blair is very fond of "I say this to you" or "Let me be clear".

Remember that 50% of statistics are meaningless. So, if you are intending to use statistics - and some well-chosen figures can add credibility and authority to your arguments - be sure that you understand them, that they are meaningful, and that they are both reliable and up-to-date. Be ready in the question and answer session, or if approached later, to be able to source your statistics and supply the full context.

Make clever use of the pause. If you expect laughter or applause or you would like to create a sense of drama, pause for a couple of seconds, before continuing your speech.