I rarely have a map as such when I write. I have a good grasp of what's going to happen -- always the beginning and the end, and then any number of scenes between them -- and so what I do is usually just sit down and wing it, for want of a better term. Ideas happen while I'm writing, and if they're good I go with them, and if they're not so good I hopefully ignore them. I can think of a few times when I've had to delete handfuls of paragraphs or even pages, but fortunately that doesn't happen very often.
I can only think of one time where I actually made the effort to write an entire outline. It was for a long-ago draft of the MO, and if I searched hard enough through a few boxes in my mother's attic, I'd probably find it still there. I recall actually sticking to the outline more or less faithfully, though obviously I must have improvised here and there, because an outline can't cover everything.
No, I'm wrong -- I just remembered two other occasions where I plotted a complete outline. It was for 2 books that were planned to be non-sequel companions to each other, and which never went anywhere except for some incomplete scenes and I think the beginning of one of the books. I definitely still have those outlines on my computer; I have fantasies about returning to them one of these days.
Just last night I finished the 7th chapter of the NT, and I actually don't think I had any idea what was going to go into it when I began. My protagonist, Samantha, a high school student, likes the new boy who moved in across the street, and I had had this vague sort of notion about what the scene was going to look like where he finally asked her on a date. But I wasn't sure how it would happen, or where it would take place, or at what point in the book it would occur. But like the story was alive and evolving as I wrote it, it turned out that Chapter 7 was the place where it happened.
Okay, technically it happened right at the beginning of Chapter 8, but whatever.
I've never spoken to other writers, so I have no idea how the writing process goes for anyone else. I suppose there are writers who map everything out to the tiniest detail, and I'm sure there are others who basically improvise from start to finish. I'm obviously closer to that last example, but not all the way there.
I'll begin with a basic notion for a story, think it through for a few weeks, imagining several different scenes and bits of dialogue, probably the ending though not necessarily the beginning. I'll begin writing with this idea in my head, starting at the start of the book. If I get stuck, or if I have a strong idea for another part of the story, I'll write out the scene the way I think it will happen. Hopefully when I get to that point I'll be able to just paste it in, but of course it rarely happens that way. I am able to paste those scenes into the narrative, but typically they'll require some revision or edits first.
Rinse, repeat. Eventually I'll get to the "the end" part, which is pretty cool. I've been able to do that three times now: once each for the 2 books in the MO, and again for the WVS. Of course, getting to the end doesn't actually mean I'm finished, as I mentioned once before. Anything but, in fact.
Nevertheless, it's still a very exciting moment. It's the fulfillment of an anticipation, an eagery awaited moment realized.
To be closely followed by the first round of re-writes.