The pace of your speech is important. Make it steady. Make your words and your pauses, deliberate. Focus on the intonation and inflection that you choose. Take your time and in taking your time, give yourself the time for good quality eye contact with the people that you're speaking with. Speak at the right time.
Speak when your listeners are ready to hear. And before you speak, pause use your pause to create expectation. You have gravitas people want to hear from you and you have the time to take to compose your thoughts and make them wait. That wait will create expectation. pauses are perfect for building tension and excitement. right at the start if you're speaking, particularly if you're presenting or speaking formally to a large group of people.
Take the time to survey the whole room. Everyone who is there. Expand your bubble of attention to encompass the whole room. Bring yourself up to your full height. Relax your shoulders. Take a deep breath.
When you've got everybody's attention, then it's time to begin