Wade mentioned Scrivener, which is what I use for organizing game notes, drafts, and game-related resources. This is some of the contents of my IF-focused Scrivener project—handy folders with notes on different engines, and then a folder for each game.
And an example of the contents of a game’s folder:
I need to be able to break up my notes and drafts like this, or else I just get lost. I struggle with the Inform IDE for this reason.