I normally just do a big text document, but I'm starting to think thats not the best method for me. It can be overwhelming to keep nice and linear over time.
Create a folder. Inside it create different folders for different chapters/sections. Inside each chapter/section folder have a notes document, a markdown version document and possibly one in HTML. Also one doc in the main folder where all documents are stitched together in order. This way you can enhance and focus on each part of your work separately, view it in whole when you want to
https://www.advancedfictionwriting.com/articles/snowflake-method/
I like the Snowflake Method. You start with the core idea and branch out in a fractal-ish pattern to develop different elements and plot points. Mindmapping software helps keep it organised: https://xmind.app/
For starting basic structure, have had good luck with Plottr. If there's a complex timeline, Aeon Timeline is pretty handy. And once ready to write, Scrivener.
You might look into mind-mapping software like gingko, nulis, minder, vym, etc.
If you don't know where to start and you have a big pile of text, it may be useful to run it through an LLM to summarize key points and suggest an outline. If you have privacy concerns, it can still work if you have an offline and local LLM instance in your computer.
