How You Can Increase Your Knowledge About Everything

First, do some experimentation to figure out what is the most effective way of learning for you, such as reading books, watching youtube tutorials, asking experts, or just experimenting on your own. Personally I found after various attempts at different things, that reading books and experimenting on my own seems to the most efficient, so I tend to focus on that.

Secondly, make a prioritized list of the fields of knowledge you want to learn. That is, in what order you want to study them. You can not study everything at the same time, but often one thing will lead to the other, so don't be too smart about where to start. Just do a basic prioritization based on your interests.

Thirdly, figure out the best sources to get really good, high signal-to-noise materials. The form of materials will differ you answer to the first question (your most efficient way of learning). In my case I found that a certain book publisher specialized to my field, had consistently really high quality content, in a readable form, so I focused on buying books from there, a few at a time, every time there was a discount etc.

Fourthly, start consuming the content. While doing that: Focus on learning the principles of the field! This is totally fundamental. If you learn the principles, you will have a structure on which to hang detailed knowledge, which will be a very easy process. Just throwing in low-level facts without understanding the principles, will be a total mess, and you won't be able to remember much. The book of Proverbs in the Bible (14:6), says "Knowledge comes easy to the discerning [one]", which testifies to this fact too.

Fifthly, remember that typically you will learn more easily if you don't stick solely to one source of knowledge, so do at times mix with other sources and even learning forms, such as practicing things (or I should say, especially practicing things!), discussing with people, etc etc. This makes sure that you don't get "snowed in" with a too narrow understanding on the subject.

Sixthly, revise your learning method and priority list of things to learn every now and then. Try to thing actively about how you learn, so that you can spot any faults in your habits, workflow and practices are early as possible.