All characters are "distinct" unless they have the same name and appearance, but how do we make them MORE distinct. First, make sure that the character's 4 core attributes are clear in your mind and/or apparent to the reader. These core understandings are :
- The character's desire(s) - What is the thing they want for themselves, something they will fight and struggle to acquire or achieve.
- The character's goal(s) - People have short-term and long-term goals, they aren't necessarily the same as their desires. They may desire to please a parent or loved one through some selfless act but have a separate goal closer to their heart. Note here that the goal may change as the stakes in the story change.
- The character's secret need(s) - this can be the same thing as the character's desire or goal, but in stories with some kind of epiphany or self-discovery... the protagonist eventually exchanges their desire/goal for their need. NOTE: the character may be unaware of the need- it is critical the AUTHOR know though. In Star Wars, Luke's desire was to go to the academy and learn to fly. He sympathized with the rebellion but wasn't motivated to join the cause. When his aunt and uncle are killed by the evil empire, his desire for revenge pushes him toward his need, to find purpose in social responsibility and become a user of the force. So, Luke's secret need was to become a Jedi.
- What are the stake(s) for the character - these are the things the person cares about. What are the particular object(s) / person(s) / ideal(s) that when threatened or compromised will catalyze the character to defend them? It's critical that the characters have stakes they are unwilling to give up easily because it's the antagonistic threat toward (or existential compromise of) that "thing" the story will joust over. Thematically speaking, this is the win/lose consequence that marks the story's resolution apex. Meaning, when there is no longer any threat or the heightened threat is reset to the status quo, the story ends. The "stakes" for each character are the win/lose consequence for them, and what predicates their engagement with the plot. Note here that side characters often have a stake in the protagonist. The main story problem itself may offer no incentive to take sides. However, the fact that the plot problem is screwing over the protagonist causes the character invested in them to act. Characters will become distinct simply through these core traits alone- and I want to emphasize that knowing these are far more important than what I will call "cosmetic" characterization. Cosmetic characterization is also known as "tagging" ... tags can be asserted in many ways:
- Character appearance / props - hair / eye / skin colors, scars / birthmarks / deformities, clothing, jewelry, paraphernalia (glasses, weapons, wheelchair, leg brace, )
- Habits / ticks - heavy drinker / smoker, pen twirler, decorative pets
- Communication attributes - vocal tones, speech patterns or accents, unique words or exclamations
- Names - not just their "name" but references, titles, nicknames, and so on. Those aren't all but you get the idea, of anything to differentiate them from others in the story. For more details on the Jungian archetypes