Just one thing?

What is that one thing in your life that you want to do but are scared you will fail at or just simply have no idea where to start?

(image via Aubrey Road)

Mine is to write novels and children's books. This has been a dream for a long time but I simply have no idea where to start or if I would even be good at it.  How do we move past this? How do we get over our fears and do it?