How to keep track of your characters across a series
Somewhere around chapter nine, you stop being sure whether her eyes were grey or green, and whether the brother was ever actually named. A living cast list fixes that, and it's easier to keep than you think.
Build the sheet as you write, not all at once
You don't need to fill out a fifty-field character questionnaire before you start. The details that matter are the ones you'll contradict yourself on later: name, age, how they look, how they talk, who they love, what they want. Add each one the moment it appears on the page, and the sheet grows itself.
Capture the small, contradictable facts first
Big themes rarely trip you up. The killers are tiny: eye color, a scar, a hometown, the exact wording of a nickname. Those are the ones a reader will catch. Keep a short, scannable card for each character with just those facts, and you'll never write "his blue eyes" in chapter three and "his brown eyes" in chapter twenty.
Track relationships, not just people
A character is only as clear as the web around them: who they trust, who they've wronged, who they're secretly related to. A cast that notes relationships keeps your plot honest, especially across a series where the connections are the whole engine.
Keep the cast beside the writing, not in another app
The reason character bibles go stale is friction. If checking a detail means opening a different app or a spreadsheet you last touched in March, you won't do it, and the contradictions creep in. The cast needs to live right next to the page you're writing on, one click away.
Let each character carry across your stories
If you write a series, or reuse a world, your characters shouldn't have to be rebuilt for every book. Keep them somewhere they persist, so the cast you developed in book one is right there, portraits and all, when you start book two.
How Inkling keeps your cast straight
Inkling has a character builder that rides along with your story: build each person once, with the details and relationships that matter, and they're a click away while you write, in every story they belong to. The generator can help you sketch a portrait or a starting point, but who your characters are is always, only, yours.