Crafting Screenplay Dialogue: My Technique
The primary goal in writing dialogue is to make it feel natural and authentic. If you find that the dialogue seems forced or awkward on the page, one helpful tip is to act it out. A skilled actor can often bring even stiff dialogue to life, making it sound much more natural than it appears in writing.
The key question to ask yourself while writing dialogue is, "Is it clear?" Note that clarity doesn't necessarily mean full disclosure or exposition. In real life, people often don't explicitly state their thoughts or feelings; instead, they conceal them. Therefore, you might want to ask, "Is it evident that the characters are hiding what they're really thinking?" And are your intentions clear as a writer?
What I like to do, is to often write the dialogue with silly exposition, that is explaining the scene fully in dialogue. I then, afterwards start hiding the exposition. By doing this, I make it clear to me what the character's intentions are so I can hide them. This is almost like painting a wall. Instead of making it perfect the first time, I do this layering for the first round, and then add the second layer to hide the first one - through this - the audience starts playing cat and mouse with the characters, what is in the layer behind the conversation?
Example: Dialogue
Let's say a character is suspected of committing a crime and a police officer is interrogating them.
# EXAMPLE A: Layer One (With "Bad" Exposition)
OFFICER: Where were you on the 10th?
SUSPECT: I was at my sister's place, she can confirm it, but she is lying and covering for me.
This was my first round of obvious exposition, and now in the second round, I start hiding it.
EXAMPLE B: Layer Two (Without Exposition, the character hides what they're thinking)
OFFICER: Where were you on the 10th?
SUSPECT: It's cold in here, can I get something to drink?
In this second example, I avoid answering the question, but the suspect hints that they feel cold (telling us that they are sensitive to heat) - they ask if they can get something to drink, trying to ask a question against a question - hinting that either they are actually thirsty or they're being tactical and trying to distract the officer.