It really depends, where for some of my characters I don't bother, others, such as Isake and Kilnir, where a lot of culture/need relies on appearance, i include it within to colour the ms, but only where i feel appropriate.
True confession: My female mains and the plot idea generally spring into my mind together, and usually they're both triggered by an event or impression in my own experience. After that, I get to work making them Not-Me, and surround them with the supporting characters I need to tell their story. One exception is a character that rose out of a writing class exercise, when the teacher brought in the photo of an elderly woman and we brainstormed who she was, what problem she was facing, etc.
I focus within, sit down, close my eyes, pull inwards, I place the idea of what I'm looking for within my space, a silhouette, and see what my mind develops, the more senses involved the better. Sometimes, it develops on it's own, like a part of oneself wants to form, and it's only release is in paper. Usually the physical features fill in first, then a voice may come through, personality, smell, and texture, I prefer to work on it till it feels believable, almost an entity of it's own, if I don't believe it's real, or is too flat, then I toss it aside, though flat characters are pretty, if I'm going to write a story on it, it needs to be fleshed out. I play with it some, see how it works, etc. I kinda feel that all characters reside within, the problem is locating them, and pulling them out.
