Firstly, hone your craft. Writing success doesn't have anything to do with how fast it flows out of you or how excited you are about what you've put down on paper (screen). It's about how excited you can make the reader. Is it what your target audience wants to read?
Be realistic. Writing looks easy to the uninitiated observer. There are absolutely no barriers to entry so the market is glutted with tripe. This means you have to write extraordinarily well to even get noticed. This is not meant to discourage but to inspire the hard work it will take to write something worthwhile.