You are like unto a god, because you have the omnipotence to create literary characters. But as we all know from watching Sam Raimi’s Spider-Man, with great power comes great responsibility. This is the greatest of yours:
Before you endow your creations with any other attributes, they must have motivations. Just as actors need to determine what it is their characters want in each scene of a play or a movie, book or short story characters must have one or more needs that drive them at all times.
And, in the same way that actors do not necessarily explicitly express their characters’ desires, though they are the origin of all that the characters do, you must convey the compulsions of your characters not in exposition but in behavior.
Actors often invent back stories for their characters — autobiographical information they never share with anyone that helps them comprehend the people they portray. Benefit from their example: Examine the lives of your characters, and understand how they got to be the way they are now. That is what propels them to say and do the things they do in your story.
Speaking of autobiography, the easiest way to create a character, of course, is to pattern it on yourself. But it doesn’t take a great leap of effort to produce a personality that is much different than yours. A character need not share the same desires (and fears) you do, but you can apply them to the character’s own drives.
He or she doesn’t have to have the same ethnic and socioeconomic background, the same family dynamics, or the same educational and professional experiences, but you can draw on those elements of your life to develop someone who is quite distinct from you.
Your main character is the foundation of your story, and his or her motivations are the cement in that foundation that bind that person together, so you must develop the motivations before you do anything else — even before you formulate the plot of the story the character inhabits.
That may seem counterintuitive, but follow the foundation metaphor: The plot the character inhabits is the house, the place in which everything takes place. But what happens results from what the character does.
Only after you decide what your character wants, what your character needs, what your character must have — or he or she will die physically or psychologically — only then should you discover how he or she is going to go about getting it, and what ramifications that will have for the wider world and the other people who inhabit it.
And notice I haven’t said anything about the character’s appearance, personality, or habits. Motivation drives each of those aspects to some extent, too, so motivation comes first. I’ll get to the trappings another time.