My first visit to my kid's preschool struck me. It was quiet. Somehow a room full of toddlers was less noisy than my house with two kids. I asked the teacher, "How?" She explained that they themselves don't ever raise their voice, which models ideal behavior.
Quick kid tip: they love whispers and will pay attention when you do. So do adults.
I love the quote from attorney and founder of It's Over Easy, Laura Wasser: "If you speak softly, they will lean in to hear you. You don't have to yell. You don't have to be a dude and pound your chest."
Some of the most influential business leaders I've worked with were the ones who used their words very judiciously. One business development rockstar gave himself three times to speak in a meeting. He'd mark them off on a piece of paper, forcing himself to save his words until they genuinely mattered.
Now as a chatterbox, this is hard for me. Still, I love striving.