We think of self-confidence as a psychological problem — when we lack it. But what is it exactly? And how is self-confidence different from self-esteem or self-efficacy?

A recent New York Times Smarter Living column does a good job of defining the three concepts. Self-efficacy “refers to your belief in your ability to accomplish specific tasks,” such as “cooking dinner or completing a project.” Self-esteem is much broader. It “refers to a belief in your overall worth” independent of anything you want to achieve. Self-confidence, however, lies somewhere in the middle: “more of a general view of how likely you are to accomplish a goal, especially based on your past experience.”

So self-confidence is the positive (and realistic) belief that you are capable of learning or doing something new — something that you’ve not tried before. Inversely, someone with low self-confidence can suffer from “crippling doubt,” a negative belief that stifles effort before it has a chance to bear fruit.

How can you bolster your self-confidence? Here  are some tips:

• Get to know yourself — inside. Listen to the inner flow of thoughts, especially the negative ones about your competency. Consider them objectively: are they really true?
• Think and act positively. Positive thinking and positive actions will defy the hidden doubts you harbor.
• Counter your imposture syndrome. Regularly reflect on skills and past successes that thwart the crippling doubt in your ability.
• Get exercise. Working out is not only a way to improve your physical health. An exercise routine that you stick with is also a way to boost confidence for other goals.
• Step out of your comfort zone. Try new things that make you uncomfortable. With each successful foray you’ll gain confidence to take on even bigger challenges.
• Dress to play the part. Your clothing choices not only change the way people see you, but they can change the way you see yourself. And while you’re at it — straighten up your posture. This can improve your self-image, too.
• Practice and prepare. Nothing boosts your confidence like the practice and preparation that increases competence to achieve a goal.
• Start small. Set a modest goal, which you know you can achieve. Meet that goal and go onto the next. With each little success, you’ll have more confidence to take on bigger challenges.
• Live your values. Know the principles that best govern your life. Living in accordance with them will keep you going in a positive direction.