So maybe a weird question, but I feel like I'm at a loss honestly:

What do you keep in your DM notebooks?

I'm new to DMing (in general) and running "Waterdeep, Dragon Heist". In preparation, I purchased a 250pg notebook to help keep track of "things". But idk what those "Things" are yet. For reference sake, my party is in Ch 1: Finding Floon. The notebook has mostly NPC information and a description of what they look like based on what I want them to look like, and anything information about them that is "generic" atm. I'm just really confused what else I would include or make note of. Any help or insight as to what one would jot down, besides the obvious Renowned for each of the Factions, that'd be awesome!

TIA!