Every character has a key. It’s taken me a long time to learn this, though I’ve been doing it, unconsciously, all this time. It is one thing, or a collection of things, that is the thing that makes them individual, makes them unique. It is the clue to the way they behave, the way other people see them, they way they react to everything.
It could be a childhood trauma. It could be a character flaw. It could be a passion for the interior paintings of Vermeer (which are lovely). It could be a hatred for dogs. (I don’t hate dogs).
You don’t always have to say what the key is, but you should know it. You may never have to explain it. Sometime it might be better if you don’t, and you leave ten reader to discover it for themselves. But it should be in your mind all the time you write this character.
You don’t always know it at the start. I don’t often know the key to my characters at the beginning. But the more I write them, the better I get to know them and soon the key becomes clear. By the time I write the second draft, I know.
I’ve only just discovered the key to one of my characters now. It’s at the end of the second draft, and I’ve only just found it. However, given who and what they are, it’s hardly surprising. But now I have it, I understand their actions better, and I understand why the other characters react to them the way they do.
This character had been awkward to write. I didn’t know why. Then today I discovered the key, and realised that’s what they needed, then, when I thought about, realised that was what I had done for all my other characters too.
Find the key. It’s vital.