In the 1932 film, Grand Hotel, Greta Garbo said, "I vant to be alone." Actually, what she really said was 'I want to be alone', but I needed you to hear the Swedish accent. (Anyway, I digress. It happens.)
Like Greta, I too prefer to be alone. The thing is -- I never am -- even when I am. You see I have all these people hanging out with me in my head. Just as in real life, I don't necessarily like them all, but what can I do? I created them, and now I'm stuck with them.
Before I can put characters into my stories, I have to get to know them. You spend a lot of time learning about the person you plan to marry, and you interview a potential employee before trusting him with your business. It's the same with characters. I need to know who they are before I plunk them into a novel, so that I'm sure they can do the job.
Initially I may be drawn to the sound of their voice or their manner of speaking. It could be the freckles on their nose that first catches my attention. It might be a funny habit or a dry sense of humour. Perhaps it's the way their mind wanders or how they anger easily. Maybe it's their preoccupation with money. It doesn't matter. The point is that little by little, I get to know them, until eventually I am as familiar with them as I am with members of my own family. I know how they will react in a given situation, what they will say, what they will think and how they will feel.
And though much of their back story won't ever find its way into the novel, I know their background too. Anecdotes and incidents that explain why they are who they are. Many authors write this information down -- kind of like a police suspect board. I just keep it in my head, and though I might not share it with my readers, every piece of information helps the character maintain his or her identity. They aren't flat paper cutouts; they are individuals with personalities, wants, needs, likes and dislikes, flaws, and strengths. They have a past and a future. (Well, unless I kill them off.)
The tricky part is finding out how the characters respond to each other. How do they play together? In the same way that you as a party host consider how guests might get along, I as a writer must consider the same question for my characters. The truth is I often don't know until they come together in a scene. I have an idea about how I want the scene to play out, but if the characters respond credibly with each other, something completely different than I had planned could happen -- and the story takes an unexpected turn. Surprise!
You're probably thinking I'm being silly. After all, I'm the writer. I can make anything happen that I want. I can try, but if I force my characters to react out of keeping with their nature, readers aren't going to buy it, and the story will fall flat.
To avoid that, I must constantly become the characters I have created. Before they so much as raise an eyebrow, sigh, or mumble, I have to dive into their skin and perceive the situation from their point of view. Then when it's the next character's turn to take the stage, I hop into their skin. So, if Maeve snaps at Declan, I have to become Declan and evaluate the situation from his perspective and within his nature, before he reacts. He isn't going to do or say what Bradan would, nor the queen, nor Enda, so I can't have a generic, preconceived response -- even though that would guarantee the plot moved on as planned. The only way I can get my characters to play their parts credibly is to become them, and if that means altering the plot accordingly, so be it.
It's like putting on a one-woman show. It's a wonder my mind hasn't turned to mush. Some might argue, it has.