If you died tomorrow what would the world miss out on? What legacy that you left bottled up inside you wouldn't grace this world? Don't hold back. Don't allow fear and uncertainty to stifle what you have to offer. Things can end in an instant. Live life to it's fullest and reward this planet with your ideas, with your words, with whatever it is that makes you yearn to reveal. Someday will never come, and yesterday is already gone. Do it today! Think of it this way. Even if you fall on your face you're still moving forward as far as it takes for you to reach the ground. Standing still goes nowhere.
I challenge you to grace the world with all you have and desire to reveal. There are many who are waiting to welcome it.