I think most artists, creative people, entrepreneurs go through very rough patches when they're young which then causes a lot of us to not do publicly what we were meant to do. In fact, I think we often hide behind "safe jobs/hobbies/days" whilst secretly engaging in our real passions/pursuits.
But when a person finally believes even just a little in themselves to say "My talent is worth something - I am worth something" and then does something (no matter how terrifying or impossible) the result is always magic and life changing.
So what is it in you that needs to come out? Even if you think you don't know, you do. And even if you think you don't know how, you do. You don't need to know everything, just one thing. Act on that and everything follows.
For more related posts read my article "Belief and Action" and listen to the Boss Lady Podcast from SXSW this year in which Emira & Lauren, Jenny Hart, Vickie Howell, and myself speak to what it's like to run your own creative business.