Your dialogue can make or break your novel--something I am learning the hard way as I work on the second draft of The Last Bucelarii Book 1: Blade of the Destroyer. Reading over my dialogue, I'm discovering where I'm going wrong with the way my characters carry on conversations. Not only is there a lack of emotion in some places where things should be pretty raw, but also I find myself using fluffy dialogue.
"What the heck is fluffy dialogue?" you may ask. Basically, fluffy dialogue is anything that is unimportant to the story.
Dialogue should be included for a number of reasons:
It should tell you more about what a character is thinking.
It should give you more insight into the character's personality and motivations.
It should establish relationships between characters.
It should show emotion and be filled with tension.
Fluffy dialogue--or marshmallow dialogue, as some writers like to call it--has elements of the above, but those elements are usually lost in wordiness, useless phrases, curses, and unnecessary additions.
Think about this sentence:
"If I ever see you again," Jack snarled, "I'll kill you."
Simple, concise, and pretty much says what the character is thinking and feeling. Now examine the sentence below.
"God damn you, Charles," Jack snarled. "Don't ever let me set my eyes on you if you value your life. If I ever see you again, I'll kill you in a way that will make your ancestors shudder."
Same meaning, but WAY too long to say something simple. It does give a bit more insight into Jack's character, but it's too much for what you're trying to communicate.
To keep your dialogue from becoming fluffy, keep it short and simple. Only include information that is necessary--both to the development of your character AND the story. Once you have that, trim everything else out.
Select a random page from your WIP and read the dialogue aloud. If it doesn't sound like something that you'd say, it's probably in need of a bit of polishing. Make sure your dialogue:
Has conflict
Is compressed
Gives each character their own unique voice
Only gives relevant information
After that, trim the rest of the fat!
Note: 21-time New York Times bestselling author, Jerry B. Jenkins has a great post on how to write dialogue effectively.
Check out: How to Write Dialogue That Captivates Your Reader