The key to a masterpiece of creativity is to allow your gift to work. Many creative people spend too much time agonizing over details which do not contribute to the work itself, and often end up diluting its value, and the driving force behind this is usually fear: fear of failure, fear of mediocrity, and fear of missing some questionable standard of the various formulae of their particular craft. Nearly always this leads to creative works that are mere copies, or even worse, filled with obvious contrivances that while intended to improve the work instead expose it as the product of a hack and a coward. This is usually more obvious in written works, and is patently obvious in sales, but the discerning eye and ear will notice it elsewhere as well.
Give yourself permission to make mistakes, but more importantly, allow yourself to dare to be great. Stop holding back, and pour out what God put in you already.