This one action builds rapport and makes people love you and believe in you.

Confidence can be passed and morphed onto others. This is great news for leaders and for those they serve. Confidence, like any other value, is a learnable and teachable skill. It simply requires practice and experience and proper beliefs.

Note that when it comes to good salesmanship and leadership, it is also one of the most important and underrated qualities someone in sales and leadership can have. It is often left unspoken — those without it suffer and eventually capitulate and/or are let go.

Confidence is a way of being in the world, to the world, for the world. And it is enthralling. We find confident people more believable and far more seductive. We listen to them unconsciously because they are that much more interesting, emphatically explaining to us their point of view. Strangely and sometimes unfortunately, even if supremely confident people do not have the data to back up their claims, we listen to them anyway. Thus is the power of the confident orator. Facts are potentially negotiable with confident people — ask any ambitious politician.

When it comes to leadership, sales or any job title for that matter, your confidence level is the average of the five most confident people you hang around with the most.

Confidence, like any emotion, is contagious. You can catch it simply by being around other confident people. The more you hang around with confident people, the more confident you will become. Confident people can positively infect someone unconsciously simply being in their presence for extended periods of time. They will talk about their desires, their goals, the fun they’re having, their travels, their latest wins, their plans for the future.

Further, they will talk about their losses or their once-perceived losses and discuss those as well. Confident people look at their losses as important lessons learned, to hopefully never repeat. They share these lessons with others so that they, too, can learn from them and not experience them themselves. These are painful moments that we’d rather not experience again, especially when it comes to deep losses in health, wealth or relationships. Nonetheless, confident people have the chutzpah to discuss these openly as a means of teaching others. If they are supremely confident, they will write them down and share them publicly with anyone who will listen, as Warren Buffett does in his Annual Letter to Shareholders.

Like creativity, confidence is a bottomless well.

It ought to go without saying: confidence is a self-fulfilling prophecy. Just like creativity, the more you express confidence, the more of it you get. And like creativity, confidence is a bottomless well if you believe it is.

Its opposite, repressing confidence or rarely expressing it, the less of it you display, the less others perceive you as confident. This negative, repressed expression undermines all of your thoughts and efforts — both personal and professional. It is debilitating. In fact, there may not be a more pernicious thing to do to oneself than to repress or rarely express your confidence in what you do and what you say. It is everything.

Let’s explore Warren Buffett and his confidence further. Buffett has a stoic confidence in himself and his abilities as an investor and leader and financial manager. Buffett has been plying his trade for 60+ years, starting out as a hedge fund manager way before they were cool and anybody had heard of them.

He also taught finance at the University of Omaha. He taught finance, by the way, in order to further explore ideas and to get comfortable in public speaking. Few know this, but Buffett was once shy and very anxious about getting up in front of a group and speaking. This is a far cry from where he is today, speaking to over 20,000 people at once in person in Omaha each May at the annual shareholder’s meeting.

Buffett knows his core competencies: investment decisions; business analysis; financial management; leadership. He also knows what he is not good at — or rather he chooses not to be good at — and he hires out for this. He says it in each annual letter to shareholders: we do not provide management. Every business Buffett and Munger buy must have management in tact or else there is no deal. Buffett tells you what he stands for and he tells you what he stands against.

Publicize your mistakes.

Further, Buffett trumpets his mistakes. Most financial managers never publicly share their mistakes with others. In fact, most business managers would never publicly share their mistakes with others. Buffett puts his mistakes in writing. These mea culpas are public admissions of guilt for investment decisions gone awry.

What good comes of this? Why would Buffett — of all people — write down his mistakes each year and share them with anyone who will listen? Public admission of guilt in poor decision-making closes the loop on the mistake. It puts the hammer down. Without mistake admission, the loop remains open like a wound. The best way to close it, to heal it, is to admit it in writing, and then move on. Plus, after you admit it, talk about it with others and analyze it, you feel better. Additionally, it makes you humble. You’re not as great as people make you out to be, even if you are Warren Buffett, one of the greatest investors of all time.

Buffett hangs around some of the most confident people on the planet: Captains of Industry; Masters of the Universe types. Buffett is in the enviable position of getting to choose who he hangs around with the most anywhere in the world. His partner, Charlie Munger, is at the top of his hang-around-the-most-with list. Charlie is even more confident than Buffett is though Munger has a tough time getting around. They both read, read, read, and explore various ideas with each other. And they’re both tap dancing and laughing all the way to the banks they’re deeply invested in.