Wherein I yet again pretend to know what I'm talking about.
How do you develop a character?
(By that I mean the fictional participants in a novel. If you're hoping for some secret way to develop your own personal character... um... go ask your father. Unless he's a jerk, then ask your mom, granny or that one teacher who wasn't a total loser. ;-P)
It's a deceptively simple question. You can probably picture your character in your head down to the color of the ink he used to doodle on his shoes (I write YA. Teens doodle on their shoes, okay?). The problem comes when trying to translate what you see and know about your character to the page.
You k-n-o-w, know your characters. You breathe them. If you've laid the groundwork, you know their entire history from conception to death and have pulled out the most interesting moment of their lives to put on display.
The reader knows none of that. They don't see the character in color or hear their voice. They get black and white words - that's it - it's up to you to make those words dimensional. But there's a catch. You can't just come out and tell your reader everything about your character; you have to sneak the info in when they're not looking. Otherwise, you end up with something roughly less entertaining than your 10th grade Geometry book. (Sure Geo will give you a clear picture of something's dimensions, but no one will be awake to see it. All those shapes and angles *shudder*.)
Sadly, the only way I know how to illustrate something is by example, so here goes:
We have two characters: Fitch and Angela. Fitch scrapes by. Angela's older, somewhat protective of the young man. She's known him since he was a kid, and he's figured out that she's someone he can go to when he's in trouble. Fitch has a lot of bad memories from his childhood because he came from an abusive home.
All the information you need about the characters is there, but the presentation is dry. For it to work in a narrative, you need to find something more compelling. Hopefully, I did:
Angela squeezed his arm, a mark of protection against memories and monsters he'd spent years trying to slay. Sometimes Fitch still looked like that filthy, half-starved, ten year old who showed up on her front step in a stained baseball jersey and a pair of his sister's hand me down jeans. He was more embarrassed by the glittered heart on his back pocket than he was the black eye and bloody nose.
He told her once that was the last time he ever ran away from something he was afraid of. And it was the last time he ever left anyone behind.
I think that pretty well covers all the points I wanted to convey. The memory of a humilated 10 year-old seeking refuge establishes their relationship as well as giving the reader a hint that something terrible had happened prior to his arrival on her doorstep. It gives a clue as to why (in the scene I took that out of) Fitch stepped into a situation most people would have run from to help a total stranger. He wasn't able to help his sister and something bad happened; he's decided to stop those things when he has the chance from now on.
It's the little hints that tell the reader the characters on the page aren't just confined to the page. They had lives before the Prologue and their lives continue after the book closes. That's what makes people care about a character rather than questioning his motives.
"Guy picks up a young woman and kid from the side of the road and drives them to the backside of beyond" could make a reader wonder about the young woman's sanity for getting in the car with him, or the man's motivation for picking up a hitchhiker.
But if the young woman and kid are being shot at, the kid says "We ran away from Daddy," and you know that the guy comes from an abusive home, then it makes the situation clearer and more believable. In that case, it makes sense for him to pick up this stranger and take her to the one place he ever felt safe because he knows that Angela takes care of people when they're in trouble.
Just like it might seem strange for a woman to answer her door at 3 in the morning in the middle of nowhere, but if the reader knows that Angela has a history with Fitch and that she's used to him showing up when he's in trouble, it makes more sense. The clock no longer matters because the reader knows she's the unconditional caregiver.
Packing maximum information into minimum words will help you draw your characters convincingly. (Think how much information you process in the time it takes you to think of any one person. It's a lot, and not confined to physical appearance.) It's also one of the things that makes writing so darn hard. You have to work with those pesky words until they fit just right into the spaces you've created.