Ha! I give a lot of professional talks and since I hate hearing people read papers (though not as much as hearing them read Power Point slides) I try to have an outline and ad lib around it, often with audience participation of some kind. But before I can do that - I write it all down as a narrative.
I guess I'm just weird. The brain doesn't work if the fingers aren't typing. (And even then it isn't guaranteed....)
I never outline and I'm so happy to hear that I'm in the majority, not the minority. I start off with a basic idea of plot, usually know who the victim is up front and that's only because the victim shows up in the beginning of the novel, and because it's a series I also know the main character. I often think I know who the killer is, but it changes towards the end. I read a review by someone of my book recently (a blogger, not a media reviewer) who said she knew immediately who the killer was so stopped reading. My first reaction was "wow" and I didn't know until page 300.
I don't always work with an outline, but I do have to have some idea in which direction the ending will go for me to even take on a story. If I can liken writing a story to a vacation, I have to know my destination.
At some point, I will have to outline the character's motivations and the third act, mostly for cohesiveness and clarity.
A little of each. I start with an idea, write a few pages (maybe as many as 50.) Then I go back and outline based onwhat your subconcious had put out there and the characters it has created. I locate my theme, write downt the preliminary outline then continue from where I left off--unless I have to go back and put more things in. Before I agree with my subconcious to go off on a tangent, I consider what it might do to the rest of the book. Does it enhance it or screw it up? (If I decide not to use that part, put the character or the plot twist away someplace and use it as a different project. When I get to the end, I rearrange the scenes for effect. (Although sometimes after that first 50 pages, I know exactly where it's going and how to get there. But always, in the end, I rearrange for effect.)
As to whether I start with plot or character? I think I'd have to say I start with character, but for me the plot and the unfolding of the plot is the most important thing in a good read.
I like Angela's idea of having something ready for when you hit the point of agony. I'm not sure that I do that because I have often come up on points of agony..
As to Grace's comment that someone told her that she, that person, knew who did it immeditately, even though the author didn't know. That is quite possible, because very often the writer didn't know because she or he didn't see what might have been obvious from the beginning.
If you want to read a book that will really have you guessing, and be wrong unless you happen to guess right, because you will, as a reader, have many very good guesses try, *Songs of Innocence* by Richard Alias.
I'm reminded of a line from the movie, The Wizard of Oz, when the Scarecrow says, "some people go this way, some people go that way, then again some people go both ways." Once I have an idea for a story I'll outline a few chapters, then write, outline a few more, write, etc. until I'm finished. Along the way I'll add to outline of old chapters whatever I think I would have written if I knew then what I know now about the story. I revise chapters whenever I feel like it; I can't wait until a first draft is done. I probably waste a lot of paper this way and I feel guilty about that, but not enough to change...
I like creating a skeleton first, even if it's only the first part ("shin bone's connected to the knee bone") or a middle part of a longer work. But the "meat" of the story, that's the most fun to write - sitting in front of the skeleton and throwing stuff at it to see what sticks. It's a lot like that old free writing exercise, where the teacher gives you a photograph and tells you to write a story about what you see. The skeleton is the photograph. But the "meat" is where your voice really gets going.