As I work on preparing my sandbox I find that the tools I use impose their own logic and workflow. If I just jot notes in a notebook, I end up with a lot of ideas, but basically just a brainstorm. If I try to work in a text editor, I keep trying to write whole stories, but end up writing a lot of text that is (at least to my style of role-play Refereeing) quite useless.
An interesting tool I've found while working on a "codification" (if you could call it that) of the character generation process in our D&D game is the humble spreadsheet. With a spreadsheet you're automatically in the world of semi-random generated tables and ideas that can be slotted together modularly. However, the spreadsheet still imposes the need to be brief with your descriptions since there's just no room for whole stories. Also, the spreadsheet naturally gives itself over to a focus on the key elements say of an encounter, a monster, a piece of treasure or whatever it is you are using in your adventure. Finally, it imposes non-linearity, since each piece of a spreadsheet is interchangeable and available as an independent data point, while text is linear and imposes an authorial logic.
Anyway, after wasting two evenings writing text, I've decided to just stick to a spread sheet for now - not least because my laptop has recently started to become more and more important as a refereeing (DM) aid in my games over the last year.