Well before I start writing, one of the plot ideas I've scribbled in my 'Ideas' notebook has usually been swirling around in my head for a while. Odd scenes, characters, dialogue etc. So when I sit down to start writing I have some key points already established.
I'm a plotter. Have tried pantsing it, but it just doesn't work for me. So the first thing I do when starting a new ms is cover a school exercise book in plain paper, and write in black on the cover my working title.
Then I start plotting. Yep, the old fashioned way with pen in my notebook. No computer yet - I actually find it much easier to be able to have my notes on the desk beside me while I write.
Back to plotting... I've found Paula Roe's Write A Novel in Three Months suggestions helpful for this. I use the following headings to get the basic idea down:
Images that inspire (glued in)
Then onto plotting:
I note the key moments. Then I write a synopsis - I found it gets the key moments and conflicts in order. I then list the scenes these moments will occur in (just a point for each). Not to say it will finish like this but it gives me an idea of pacing and structure.
Scene 1. Nope, still not ready to write :o) I have1 page in my notebook for each scene, and I write a few sentences plotting each scene. Sometimes I'll plot the scene straight before writing, other times I'll want to get my ideas down when they come to me. But I always plot my first scene and note the hook it finishes with.
Writing! Now I start writing. I switch to my computer, but my notes are always right beside me. I write in word and write scene-by-scene. I don't worry about chapters, they seem to work themselves out as I go. I have a very strong internal editor, so I often write with my eyes closed to stop myself editing as I go. But after I write a scene, I will read through it and mark in yellow highlight where I need to come back to.
Once I have finished my ms I start my editing. And here I switch back to paper. I print my ms and use pen to scrawl my edits. The first time through usually has the big edits - moving scenes, block rewrites etc. Once I've been through my ms once, I make these changes electronically. I then send it out to my CPs.
Time to start the process again and tell my next story :o)