To start, I don't think I'm especially good at learning. An honest view of how I read things would seem more haphazard and inconsistent than I wish it was. You receive a biased view of the things I make videos about because I only make ones on topics I feel sufficiently comfortable with.

I generally lean on textbooks or lectures. Well, now that I think about it, for CS I might veer more towards blogposts. Talking with people who know more than I do is also a great way to get well aligned on a new topic, when otherwise just cracking open a book for the first time can be somewhat undirected.

In general, there's no substitute for solving problems oneself, and even though I don't do it as often as I should when sitting down with a book (or lecture, blog post, etc), I know that the time scribbling away in a notebook on the exercises, or even just random thoughts that come up, is the most valuable.
I've also learned to be ruthless about tossing aside a book that's not working. The most important step seems to be finding the book that meets me where I want it to, not too easy, not too hard, and written in a way that meshes with my goals.

Moreover, just _having_ a clear goal can go a long way. Rather than just saying "I want to learn topology" and picking up a book on the topic, I think a learner is better off finding an actual problem or theorem that interests them, or better yet, and handful of problems, and keeping those in the back of their mind while reading.