“all too often I see writers take the all-at-once approach: a character has a problem, realizes it, decides to act differently, and is thenceforth cured. Like magic! It’s exactly like magic, in as much as that’s not how life actually works. In the real world, personal growth takes time and practice.”

Great point! See Five steps to building a believable character arc

In a Writer’s Digest seminar on “The Psychology of Character Motivation”, thriller writer D.P. Lyle suggested that you should work out where all your characters start off on each of the following key dimensions:

  • Tough Guy <–> Whiner
  • Team Guy <–> Rebel
  • Artist <–> Dreamer
  • Smarty <–> Dummy
  • Blooming Rose <–> Wallflower
  • Grinder <–> Lazy Dog
  • Goody <–> Baddy
  • Believer <–> Doubter

Then work out where you want them to be by the end of the story.

Some helpful tips on getting your character’s language right:

“within five minutes of reading about your main character, we should peg him or her for what he or she is, even if he or she never mentions it.” You need to learn how people like your character speak: “every subcategory of person is going to have its own lingo and its own frames of reference”. And remember that we talk differently in different contexts/ with different people

To learn how to do this:

  • Talk to real-life people who do these jobs or fit these classifications
  • Pick up magazines written for and read by individuals in these jobs or classifications.
  • Find a support group online where people of your character’s description gather.
  • Podcasts. Listening to someone talk off-the-cuff about his profession or self-categorization will give you everything you ever need to know about how your protagonist should speak.