>>16365461
Honestly, game design has its own field, but a lot of it crosses over into other disciplines of the industry. If you want to be a good designer, you want to learn a bit about art and programming at the very least. Art (especially composition) thinks about the user's eye and how it's moved around a picture. Programming can give you a sense of how to think through and define logic that was overlooked when trying to theorycraft systems. Music and sound is also good to know on some level as it strongly impacts the player's perception of the game and parts of it in feel.
As for design itself, as anons said, board games are good for raw stuff because rules are spelled out and you can try to break them down and see how players think through problems or scenarios in a game state. You can look at these rules and try to find how they might lead to those sorts of situations. Balance and how it influences a game's state or general feel is another thing to look into. Once you design something that works well with rules and balance, then the rest is mostly making it usable so things like the UI doesn't get in the player's way and feel clunky or easy to screw up. For that, I'd suggest Design of Everyday Things, if you want a book. As it says on the tin, it's not really for game design, but design as a whole. I'm attaching it here.
Learning about the flops and almost flops of some old games and teams is a good way to get some insight too, and makes for some entertaining reads regardless. Read postmortems and you might see some things to consider or avoid. While dated, a good one I'd often seen mentioned is Thief's postmortem from 1999. From what they say, you can see how Thief was designed around particular technologies, themes, and experiences in mind all while the studio was about to go under.
There are specifics to setting up a pipeline and integrating things like art to programming, or writing code that makes designing easier to rapidly test, but that's some more specific stuff that you may need to search for as you encounter those issues. The /agdg/ thread may be able to help with that some too.
If you want to sell your game, I'd suggest reading into business and marketing. For marketing, I suggest looking at the Blue Ocean strategy, which you could try to frame with design to make games that do new or interesting stuff and don't rely on your competition. I'm still experimenting with marriage of design and marketing in a way that isn't the shitty fads of lootcrates, microtransactions, and bugman merch.
This goes in hand with what everyone else was saying; play shit and see what clicks and what doesn't. Get an intuitive feel for what you want to experiment with. Sticking too much with books and papers will detach you from the process if you don't go out into the field and do your own research. Books and articles are good if you want some potential frameworks that exist for general purpose stuff, or if you want something to spotlight things you might have missed in your own research.