I like to use traits from people I know but only traits. I want my characters to be unique individuals. What happens is I observe a specific character trait in someone I know and find that the trait would be perfect for one of my characters.
In fact, I put a bit of myself in all of my characters. Understanding many of my own strengths and weaknesses makes it easier to create characters that are more believable. Yes, even the villains. After all, isn’t there a bit of villain in all of us? Don’t we all sometimes wish we could do what our villains do?
What about you? Do you use yourself or people you know to create your characters?