Personally, I’m a firm believer that it’s the characters that make a story great. You can have the worst plot in the history of the universe, but if you have interesting characters, a reader can look past a boring plotline.
I am not a fan of listing off personality traits when you first start to create the character. I think it gives a very narrow definition of who the character is and doesn’t leave a lot of room for development and change.
To start, I come up with a simple phrase to describe their role in the story. Let’s say my character is Batman. I’d call him a “millionaire vigilante”.
Next, I think about where they come from. Where would the character have to come from in order to wind up in that place? Why would Batman become a vigilante? How did he become a millionaire? I would answer those questions. His wealthy parents were killed by a criminal, which left him with a strong opposition to crime and injustice.
Then, I fill in all of the holes in the story by asking myself more and more questions about the backstory. I add in an enormous amount of detail during this stage. Make the backstory as detailed as possible. Real people have detailed backstories and memories. The character should as well.
Next, I come up with a list of likes and dislikes. Now, I see people using a likes and dislikes list for food preferences and such. But, that is not what I mean here. Come up with a list of traits that they respect in other people. Come up with a list of traits they don’t like in other people. Keep their backstories in mind as you do this. Oftentimes, those would affect how they perceive the world and the people around them.
After this, I usually have a strong idea of who the character is, but they still do not have a voice. Every single person speaks in their own way. Some people try to be funny in every sentence while others are solemn. Some are quiet. Some never shut up. Think about the way they interact with people and hoe they’d want others to view them. Think about where they were raised and what sort of accent they’d have. Do they use slang? Are they loud? What type of sentence structure do they use? Are they precise or detailed? Do they exaggate? What about manneurism and body language? How does their communication change when their happy, sad, or angry? The more detail you put into this stage, the more unique dialogue and interactions you will get from the character.
After this point, I list off the traits. I make sure some of them are self-contradicting. It makes them more complex and, in turn, realistic.
Then, I try to take as many personality quizzes online as possible as the character.
Finally, I come up with the less important things like food preferences, favorite colors, and favorite animals, the more trivial aspects of a character. Still, creating them helps make a more realistic character.