The biggest pitfall to avoid is not writing. Not writing is really, really easy to do, especially if you're a young writer. The hope that elves will come in the night and finish it for you, is a very common one to have. That is my main recommendation - you have to write, and you have to finish what you write and beyond that, it's all detail.
Neil GaimanIt won't hurt, said her other father. Coraline knew that when grown-ups told you something wouldn't hurt it almost always did. She shook her head.
Neil GaimanI was a normal child. Which is to say, I was selfish and I was not entirely convinced of the existence of things that were not me, and I was certain, rock-solid, unshakeably certain, that I was the most important thing in creation. There was nothing that was more important to me than I was.
Neil GaimanThe only advice I can give you is what you're telling yourself. Only, maybe you're too scared to listen.
Neil Gaiman