For pretty much as long as I've been writing (25+ years), "Character Questionnaires" have been popular. Sometimes these are called "Character Interviews" with the questions phrased as questions for your character.
Some people love to fill
these out with tons of little details. And if you enjoy using these types of questionnaires, go for it.
For me, though ... they're overkill.
Questions I've seen on these Character Questionnaires include "what's their favourite day of the week?", "what are their feet like?",
"how ticklish are they?", "how do they go to sleep and how do they wake up?" and an awful lot more that I can't imagine ever making it into a story.
Plus, many writers get a clearer picture of their character once they start actually writing. So you could spend weeks on character questionnaires only to realise, two chapters in, that your main character doesn't really fit all those
random details you made up.
So what can you use instead?
One option is to pick a few of the more interesting questions from a character questionnaire ... ones that might have actual story potential.
"What are their biggest secrets?" could be hugely important for the plot, for instance. "What's their view of lying?" could give real insight into their values (and pave the way for conflict in the story).
But you'll also want to make sure you've got the important details written down for all your key characters.
For that, I've made a new little freebie ... "Character Cards". They're like a tiny character questionnaire that just covers what you need to know about the main character, antagonist (villain), and supporting characters in your novel.
