Interesting trick novelist Hilary Mantel uses (from
The New Yorker feature on her):
When she's starting a new book, she needs to feel her way inside the characters, to know what it's like to be them... Sit quietly and withdraw your attention from the room you're in until your'e focussed inside your mind. Imagine a chair and invite your character to come and sit in it; once he is comfortable, you may ask him questions. She tried this for the first time when she was writing "The Giant, O'Brien": the giant came in, but, before sitting down in the chair, he bent down and tested it, to see if it would take his weight. On that occasion, she never got an further, because she was so excited that she punched the air and shouted "Yes!" but from then on she could imagine herself in the giant's body."
Try it, see how it works.