Most managers underestimate themselves. Because the job of getting people to work at their best is often peppered by mistakes, shortfalls and failures, managers may be reminded more of their shortcomings and limitations than they are of their strengths and possibilities.

I once knew a woman who had an M.A. in English from a well-known university. She loved fiction and poetry, and we would frequently talk about books. She often said that she would like to write a novel someday. One day I encouraged her to take the first step by writing a story. To my surprise, she expressed reluctance, explaining that she wasn’t ready to try it. I was puzzled by her attitude, because she was a student of literature and a thoughtful, intuitive person. I had seen examples of her writing. It was quite elegant – far above the norm. She simply believed that she couldn’t do it. And so she never did.

By contrast, our company once hired a young computer programmer who declared that our new web-based program needed a content management system. I knew he had no experience with this kind of programming, but he claimed that not only could he do it, he would create a generic, self-customizable content management system that would become a product in its own right. So we gave him the project. He made a lot of mistakes along the way, but it was amazing to watch him learn. And in the end, he did what he said he would do, even though he’d never done anything like this before.

The difference between these two people is self-confidence, the belief that you have the ability to accomplish a difficult task.

So…which person would you bet on to succeed? The super-talented individual who believes she can’t? Or the person who lacks know-how but is convinced he can?

Believe you can, or believe you can’t. Either way, you’ll prove yourself right.

When you’re faced with the challenges of leading people, it’s easy to doubt yourself. You know you have certain strengths, and you’ve accomplished many things in your life. But you also know you can’t be good at everything. You may feel it’s foolhardy to ignore your limitations.

Don’t sell yourself short! You have imagination. You have energy. You can build on what you already know, learning as you go. You can work hard and refuse to quit. As the German poet Goethe wrote, “Whatever you can do or dream you can, begin it; boldness has genius, power and magic in it.”

To help you be strong for leadership, create the three power lists of a self-confident manager.

1. Make a list of all your achievements – everything you’ve ever done in your life that you’re pleased about. Take your time. Start with you childhood. You’ll find that you’ve probably forgotten about many of your accomplishments! Each time you catch yourself saying, “Oh well, that’s not much of an achievement,” banish this thought from your mind and write it down anyway. When you’re sure the list is complete, slowly review it. As you consider each item, positively affirm it and why you’re pleased with it. Do this for each accomplishment, without exception.

2. Next, make a list of your knowledge and skills. Once again, include everything. The list will be longer than you thought.

3. Finally, make a list of your strongest traits and attributes. Don’t be modest!

4. Once the three lists are complete, say to yourself: “I’m strong for leadership in many ways. I’ve learned a lot and I’ve accomplished a lot in my life. With effort, I can do almost anything I really want to do.” Repeat these sentences three times every day.

It’s easy to lose sight of what you’re capable of. The three lists are a realistic audit of your true capabilities. Create all three and save them for future reference.

You’ve already earned the right to be self-confident and strong for leadership. Acknowledging your strengths and accomplishments is like putting money in the bank. You don’t earn interest if you discount the good things or fail to give yourself credit.

Expect great things of yourself, and you’ll find it’s easier to accomplish them.