I usually jot down ideas - about 2-3 sentences just to summarize it. I then roughly outline it just to ensure that I have enough to say to write a full-length novel. I work better with visual aid so I often organize story arcs, subplots, and characters with a mind mapper (either web-based or just a pen and paper type flowchart works). Before I actually start writing it, it helps if I let it all play out in my head like a movie. It helps with character profiles, setting/locations, overall mood. I use a similar process with shorter works of fiction. Once I have the bones all in place, I just go with it. Sometimes additional characters/plot lines present themselves. Sometimes I toy around with alternate endings/outcomes just to keep it interesting.
I'm always trying to refine the way I work. Mostly, I have a notebook with tons of seemingly random scribbles and I patch it all together.
Mind mapper definitely helps. Also a writing soundtrack of sorts helps with the tone/mood.
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Bad Juju: Vol. 1 (dark fiction/horror short story collection)
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