There are many good recommendations here, but I’d add that reading books about mental models is worth 10%, while practice thinking about real situations is 90%. To get practice, you can’t just sit and scratch your chin. You have to make a predction, write it down, then see how real life played out a few years down the road. It helps to write down predictions you considered but rejected and why.
That sounds like quite possibly the least effective method of learning. There are people out there who have done all that work for you. All you have to do is pick up a book, learn their models, then stand on their shoulders as you develop your own.
It maybe less efficient, but in my experience, practice has consistently been the most effective way to learn something.
If you're looking for efficient, then you'd want a well-structured mix of theory and practice.
> All you have to do is pick up a book, learn their models, then stand on their shoulders as you develop your own.
Rarely does this work for any complex topic. I can't imagine learning math, or languages, or coding by simply picking up books. IMO, these models are very similar -- they have a ton of depth that can't be internalized without practice.