Essentially I'm untrained so I just go with my imagination and try to put myself as solidly as I can into the shoes of whatever person I'm going to be playing.
You want to try and bring a character to life in an honest a way as you possibly can. It doesn't matter whether he's a doctor an actor a car salesman or a captain of a starship. If you can bring truth and honesty to that character then your audience will believe you.
