People love to talk about themselves. On dates, in the office and especially on social media, you'll often hear others trying to make themselves seem impressive.

It rarely works, says Adam Grant, a bestselling author and organizational psychologist at the Wharton School of the University of Pennsylvania.

"For the most part, bragging about your accomplishments is ineffective and often counterproductive, because people don't consider you a credible source of what you're a genius at," says Grant, who's studied human behavior for over 20 years, including "lots of research on self-promotion." 

Talking yourself up can even backfire: "Constantly broadcasting successes is not a sign of success," Grant wrote on LinkedIn last month. "It's a mark of insecurity. Insecure people only talk up their wins. They brag to get attention."

The real way to not look like a brag-a-lot is to get others to do the talking for you, says Grant: "You really want other people to sing your praises, because they're more credible, and that doesn't call your character into question."

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You can do that by cultivating strong relationships with the people around you, both personally and professionally. In the workplace, for example, you might help your manager train new hires, or regularly contribute creative ideas in your team meetings. When you're up for a promotion, your boss can then easily recommend you as someone who's a helpful, creative team player.

Lisa Skeete Tatum, CEO of the career coaching platform Landit, calls these kinds of people "sponsors." They can speak to your strengths and abilities when you're not there, she told CNBC Make It in 2022.

"I would not be where I am today if it wasn't for people who believed in me ... who saw something in me and took a chance, who helped me see things I didn't even know were possible," said Tatum.

If you're in a situation that demands self-promotion, like a job interview or a performance review, Grant recommends speaking about any accolades and accomplishments that you can verifiably prove.

Instead of saying you're the most athletic person in your family, for example, say you've completed the New York City Marathon twice. "Make sure you're sharing things that are objectively verifiable, as opposed to bragging about how you're a genius or the best public speaker in world history," says Grant.

Then, mention the challenges you faced along the way, like finding the right space or building your endurance. "Secure people are open about their failures too," he wrote on LinkedIn. "They share their peaks and valleys to inspire others."

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