As a confidence coach who does a lot of training and coaching on executive presence and effective communication, I am always quick to point out to my clients that they are most powerful when they are NOT talking.
This is counterintuitive to how most people were taught to think about communication. After all, isn't it when I'm talking that I'm communicating?!?
Think about this from a listener's standpoint - when someone is talking, what are you often doing? Are you listening intentionally, making sure to understand before you respond? Chances are, more often that not, you're either thinking about what you're going to say next or jumping in before the person was even done saying what they were going to say.
The best communicators don't say much, but what they do say matters.
One reason for this is they don't think out loud. Most people decide what they're going to say as they hear it come out of their mouths! There's no pause before they open their mouths. Effective communicators take a moment to get clarity in their minds about what they're going to say before they open their mouths.
Challenge yourself to try this - become a better communicator by becoming a better listener; a really good listener. Allow people to finish what they are saying before you jump in. Actually hear what they say. When they stop talking, take a moment to think about how you're going to respond.
Then, and only then, respond.
You will be amazed at how much simpler and clearer your words are when they come out.
By practicing this consistently, you will tell people so much more than you ever have before. Mainly, you will tell them you hear them. We're not used to being heard these days. Because of that, doing this one thing will not only bring you more calm and confidence, it will also set you apart from the crowd in a positively memorable way.