When I get ready to write, I envision myself visiting with my characters. We sit down in a darkened tavern or walk the streets of some little village or hike in the wildlands, and they tell me what is going on in their lives. I then write it down. What they tell me becomes my story. It's as simple as that, really.
I never feel pressured to write. It's something I truly enjoy doing. I suppose it's the only time I feel at peace with my surroundings.