Rule #5: Watch Out for First Person. I put down three books recently because I was annoyed with the first person viewpoint, which came across as self-absorbed. Unless you're writing in the form of letters or journals, make sure any first-person character has a good reason to be telling his story. People tend not to like people who notice themselves too much or describe themselves or seem overly aware of how others perceive them. Anyone relating a story about himself -- what he said, what he was wearing, what inflection he had in his voice or what gesture he made as he spoke some pronouncement -- we dismiss as annoying and self-important. We feel the same about characters. There are many beautiful books written in first person, but know the challenge of this before you start out, and be sure to give a credible reason why your character needs to tell his story and why he deserves an audience.
Rule #6: Don't Get Bogged Down by Back-story. It is easy to be overly dutiful and bore your readers with too much background information delivered too soon. There is no surer way to lose your reader than to answer every question before he wonders about it. Don't explain everything up front or set things up too thoroughly. Instead, let your story unfold dramatically. Clarity will emerge eventually. The trick is to delay telling back-story for as long as possible. You will find that most of it is never needed. It percolates up through the real story when the real story gets going.
PS: I usually have no trouble following #5; I, too, dislike first person narratives. But in the case of my upcoming "The Road to Frogmore," there are a few short sections told by a slave woman watching the process of emancipation. The whites around her have no idea of how she feels, so it is important to let her speak for herself. Which all goes to prove the old adage, I suppose, that rules are made to be broken.