My mom used to make yogurt. You can’t do that completely from scratch, though. You have to have a small bit of yogurt to start with, then new yogurt grows from there.

Most of my characters start with some small piece of me.

Some of them start with small pieces of people I know, or people (real or fictional) that I’ve observed.

I take the small piece–a gesture, an expression, an unexpected reaction or surprising opinion–and set it all by itself, apart from everything else about the person it came out of.

Then I make stuff up.