If you're afraid of public speaking, thinking about the RMS Titanic may not exactly put your mind at ease. But keeping the famous maritime disaster in mind is exactly what Vice President Kamala Harris advised when a young supporter asked her secret to great public speaking back in 2019.

In a clip that is recirculating on TikTok, Harris — who delivered a speech to wrap the Democratic National Convention on Thursday night — tells a group of teenagers that the key to overcoming fear onstage is remembering that "it's not about you."

Rather, she says, imagine you're on the Titanic and you're the only one who knows the ship is about to sink.

"Are you going to worry about how you look and how you sound? No, because the thing that's most important is that everyone knows what you know, because they need to know what you know," Harris says.

"So when you give your speech, you know something that you have to share with people, that they need to know."

Overcoming fear and knowing your audience

Harris' advice gets to two key points offered by experts interviewed in Make It's online course, Become an Effective Communicator: Master Public Speaking. To be an effective communicator, you must overcome the anxiety around speaking in public and focus on your audience.

By emphasizing the urgency and importance of the message, Harris urges the speaker to cut through the social anxiety of looking foolish or weak in front of peers. It's similar to advice offered by Chamin Ajjan, a licensed psychotherapist and CEO and clinical director of Chamin Ajjan Psychotherapy.

Rather than trying to tamp down on a highly aroused, anxious state, she says to harness that energy.

"An alternate way of dealing with that high arousal state is to keep it, but to shift from one high arousal state to another high arousal state. Anxiety and excitement are very closely related," she says. "They're both anticipatory feelings, meaning they're all about what's going to happen in the future. And they are both high arousal."

"So reframing the way that you're thinking so that it's less about your negative evaluation, to something positive, something that you're excited about, can be really helpful," she adds.

Harris also mirrors the experts by centering the audience, rather than the speaker.

"One of the mistakes we see a lot of people make is they're thinking about their content before they think about their audience," says Noah Zandan, co-founder and CEO of sales training firm Quantified.ai. "One of the things we love to say is ABC: audience before content. Let's be frank, audiences are selfish. They want to know what's in it for them."

Now think back to Harris' sinking cruise liner analogy. If the boat were headed for the iceberg and no one else knew, you wouldn't waste your time with noncritical information. Rather, you'd share only what you thought was essential for your audience to know.

"You have to tailor what you're saying to their needs and what brings them into the room to listen to you," Zandan says.

Want to be a successful, confident communicator? Take CNBC's new online course Become an Effective Communicator: Master Public Speaking. We'll teach you how to speak clearly and confidently, calm your nerves, what to say and not say and body language techniques to make a great first impression. 

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