For example lets take this plot seed.
I'm telling you it was no ordinary cobra. When it arose from the tea bushes it was tall as a man, and had fangs the size of fountain pens.
Thats a good start. I then write down what comes to mind. What I think would work, or be cool. Just because it gets written down doesn't mean it will get used. Its just formation of ideas. So from that idea this list comes about.
Chemical Growth Formula
Kali death Cult
Dynamiting a bridge
Noon Day Gun
I then start piecing things together in my head. What I want to include, exclude. Possible encounters and such. It forms up, or at least gives me a frame work to hang things on.
One of my settings thats been written up (and rewritten) for a long time started as this list.
Now this is just my way, to help organize my thoughts. Maybe it can work for you, maybe not. But I thought I would share one of my methods of madness.