Before I write my novel, I completely study the type of novel that I am writing. Is it Literary? What's the Genre? Is it a mystery? If so, I make sure that the sleuth, the victim and perpetrator are brought on stage early. Speaking of stage, I pretend that I am the character and I study my protagonist; the particular crisis she is in and the place where she is rooted. Then I find out what is it that this character want, what's at stake, and what does she stand to lose or gain by the end of the story. What is the object of her desire? The achievement of the goal is less important than how desperately the character wants her desire.
I think that by becoming the character, the readers will happily spend hours turning the pages once I,as the character, have tangible understandable desires , and if I make these desires as specific as possible and emphasize them throughout the story; beginning with the first line and throughout every action in the story, I believe by assuming the identity of the character, I can convince my readers that the character is a real person in the physical world. Also, this will prevent the overuse of dialogue tags, "he said/she said." Using too many synonyms can often draw attention to them, and eliminating these tags can alert the reader to the person speaking.
Dialogue should be written as it would really be spoken.