A lack of self-awareness can be extremely costly for a leader. You need to be constantly evaluating yourself, what you do well, what you do poorly, and how you come across to clients and employees.

Self-awareness "lies at the root of strong character, giving us the ability to lead with a sense of purpose, authenticity, openness, and trust," Anthony Tjan, CEO and founder of the venture capital firm Cue Ball, writes in Harvard Business Review. "It explains our successes and our failures. And by giving us a better understanding of who we are, self-awareness lets us better understand what we need most from other people, to complement our own deficiencies in leadership."

If you know you've been ignoring the voice in your head that's telling you to honestly assess yourself and your actions, check out Tjan's suggestions below.

Take time to look inward.

Tjan, who co-authored the New York Times best-seller Heart, Smarts, Guts, and Luck, says there's no way around this one: You need to meditate. "Most forms of meditation begin with focusing on, and appreciating the simplicity of, inhaling and exhaling. But these don't need to be formal or ritualistic--greater clarity can also come from regular moments of pause and reflection," he writes. You don't have to do more than relax, focus on your breathing, and think on a few questions: What am I trying to achieve, what am I doing that's working and not working, and what's getting in my way?

Organize your priorities.

Your goals and overall purpose can too easily get brushed aside. If you're not careful, losing track of your purpose can make you feel rudderless. Tjan says you should write down your key plans and priorities. "One of the best ways to increase self-awareness is to write down what you want to do and track your progress," he writes. "Warren Buffett, for one, is known for carefully articulating the reasons he's making an investment at the time he makes it. His journal entries serve as a historical record that helps him assess whether or not future outcomes can be attributable to sound judgment or just plain luck." Ben Franklin, Tjan adds, kept a balance sheet of his personal traits' assets and liabilities. He tracked his new strengths and weaknesses in an effort to calculate his character's "net worth" over time.

Talk to your friends.

It's hard to be vulnerable, and it's hard to take criticism, but you should ask your friends to call you out on your failings. Have them act as an "honest mirror," Tjan writes, to give you a candid and objective critical description of who you are. "Make your friend or colleague feel safe to give you an informal, but direct and honest view," he writes. Also, when it comes to pointing out a flaw, ask them to do so whenever you exhibit it.

Build a formal feedback system at work.

The informal, friendly critique is great, but you need to have your employees give you honest feedback as well. "Provided it is done well, constructive, formalized feedback allows us to better see our own strengths and weaknesses," Tjan says. At Tjan's venture capital firm, he has set up an annual 360-degree feedback process. For feedback to be effective, he says, you need to set up such a formal process and have someone on hand to manage it.