If you identify as an introvert, public speaking can seem like a daunting task. In fact, it's tiring and emotionally laborious to express a personality that isn't yours, says Susan Cain, the best-selling author of "Quiet: The Power of Introverts in a World That Can't Stop Talking."

But even introverts can become comfortable with public speaking if they continually practice, she tells CNBC Make It.