Many years ago, someone complimented me on my use of pauses during a speech. I stuttered when I was young. My speech therapist suggested that whenever I started to stutter, I should simply stop speaking. Then…collect my thoughts…relax… and proceed slowly again. Today, I use that same technique as a powerful tool.
One of the mistakes new speakers make is not allowing the audience time to think about what they just said. An important point in a speech needs time to be thought about. Many professional speakers as they approach an important point will give a quick pause, then make their point and follow this with a 3-5 second pause.
At first, many speakers are uncomfortable with doing this. I suggest in your practice time to exaggerate the length of a pause…say make it 8-12 seconds. Afterwards as you give your speech to a live audience, a 3-5 second pause will not be that uncomfortable.