1) Start with an elevator pitch to yourself. Is the story intriguing? Is there an interesting protagonist and challenge? Do you want to know more?
2) Commit to finishing the story. Once you begin a plot that drives you to write it, let nothing stop you from completing that last draft.
3) Don't show anyone your first draft. Whether it's to your editors or your beta readers, always put your best foot forward. Besides, they probably think you're a genius and most first drafts will dispel that notion.
4) Challenge yourself. Give yourself a word count and stick to it. Write in a genre you dislike, just to see if you can do it. The lessons you learn while doing this make you a stronger writer in the genre(s) you enjoy writing.
5) Never write to the trend. By the time you write your story and get it edited and published, the trend's already moved on. Instead, #bethetrend!