This is the first part of a series titled - New Writers
Developing character is an extremely important part of writing, and creating a realistic character is the most important thing you'll want to do when first starting a story.
So how do you do it? Well, let's just clear this one thing up first. It's not easy. Never will be, never can be. And this won't make it easy, either. It's hard, really hard. You have to commit yourself to it. Then and only then will you have a realistic, developed character.
Why do you need a developed, realistic character, though? It's fairly simple. If a story has a faceless character, one who doesn't have any character development, the reader just won't care. It's as simple as that. As a write, you want the reader to cry when the hero dies, or cry in joy when he makes the right decision after a book of confliction.
You would care if your friend died, yes? You care about your friend because you know him or her. Knowing the character will make the reader feel for him or her. That's all. Knowing that the character is "real". Real in the sense that he (or she) is like humans - I'm not loony, I'm not saying your character should become human, I'm saying he or she should be like a human. Although, they're really not much difference once you get to know a character - only one is taking over your mind and the other is floating around in real life somewhere.
When you're creating a character, remember they're real - they're just not real in the sense we usually think in. They have to be real in your head.
Making them "real in your head" however, is quite difficult. First it requires a lot of time - at least a month before you have their opinions and voice - which are two complicated terms for basically what he or she would do in any random situation life will give - stuck in your head firmly. I told you this isn't going to be easy - but please, don't drop out on me yet.
And of course, you actually have to do stuff with your character during that month or 2-3 weeks it takes. You have to get into the character's head - or maybe let the character into your head. Exercising the character's opinions and voice and views and personality (like I said earlier, just how they would act in a situation of something) is a good first step making your character realistic.
If you randomly make up something totally outrageous that your character did or does (i.e. he lives in the sewers) ask yourself, why? Give your character views and opinions (they don't have to be outrageous - just anything you can think of) and ask yourself why? Have your character do something - have him or her react to something (anything!) and then ask why?
It's the Socratic Method, and it works. Ask why of every single thing your character does, and you're starting to learn who your character is.
Wait -- aren't we creating a character, not learning who he or she is? Well, like I said earlier, your characters are real, they're just in your head. You need to explore them - because they're real.
Now unleash the power of the character.