Character is revealed via:
The narrator could state explicit opinions about the individual. However, readers often find it more satisfying to deduce the nature of a character rather than be told directly. And they can construct a character from small amounts of information. Think of how a cartoonist uses a few key features to identify a politician. Writers do something similar with words. The more original the description, the better the chance of a character who is distinctive and memorable.
Stock Characters
Some examples are the fool or clown, femme fatale, absent minded professor, villain, nerd and tortured artist. Readers can often identify them without any naming. Stock characters have the advantage of requiring fewer words and the disadvantage of being clichés unless something is done to differentiate.
Many middle-aged fictional detectives are at odds with superiors and have dysfunctional private lives. Crime writers often employ distinguishing and even quirky features to provide their novels and film scripts with at least a variation on the stock character of a detective.
Complexity
One way of avoiding cliché characters is to add complexity. E.g. Rather than a villain being predictable or portrayed wholly unsympathetically, revealing a better instinct or a moment of regret. The trick is in maintaining rather than straining credibility.
Contradiction
One way of adding complexity is contradiction. An individual might respond very differently to, say, a stranger depending on factors such as prejudice, stress,tiredness and power relationship. A person is often unpredictable for reasons that may be hard to fathom in reality, but can be hinted at or revealed in a short story
Motivation
Wanting is central to a character, whether or not this is stated directly. And a frustrated desire is often important for providing conflict and therefore tension to the story.
Secrets vs. Face Presented to the World
“We are our secrets, and, if all goes well, we will take them with us to where no-one can touch them.” Cees Nooteboom, Dutch novelist & poet
The secrets of others are both intriguing and revealing. The nature of an individual’s secrets and the lengths gone to in order maintain them says a great deal about character and the individual’s relationship with cultural norms.
Vulnerability
A mortal who is perfect tends to make for a dull story unless written as a spoof. The ancient Greeks knew this when they assigned Achilles’ his unprotected heel. People hearing this story for the first time wonder whether the heel will be the downfall of the hero, which brings tension. Psychological and physical vulnerabilities can also contribute to more interesting short story characters and especially when there is conflict between desire and need to overcome a weakness.
In real life, some emotional vulnerabilities, such as triggered phobias, are impossible to conceal from others. Other vulnerabilities might be hidden to varying degrees or only shared with certain people. Both their concealment and with whom they are shared are of interest to authors developing a character.
Three of the most important categories of emotional vulnerability are: