Though most people appreciate that information is communicated through body language and vocal tone, they don't usually realize just how much. In fact, words are only part of the message in face-to-face communication; vocal tone accounts for another chunk of the message, and nonverbals for another large chunk. As a result, we often give away more about ourselves than we intend to.
This is true of your characters, too, and your job as the writer is to convey the most important nuances in your story.
Your task, then, is to imagine spending an afternoon with your main character. Your job is to notice everything—all the details you may not have thought about before—and consider how they reflect not only how the character views herself but also how she wants to be seen. Is she sending the messages she intends to?
© 2011 Carolyn Kaufman, PsyD ♦ Psychology for Writers on Psychology Today
Carolyn Kaufman, PsyD is the author of The Writer's Guide to Psychology: How to Write Accurately About Psychological Disorders, Clinical Treatment and Human Behavior. More information is available on the book's website.