How did you self-teach?

What are your experiences with self-teaching music theory? You don't have to be a 100% autodidact to answer this question; you probably have had times when you read a book or watched a video to learn some specific idea or technique. Ideally, I'd like to compile some guides for readers who don't have a teacher.

Personally, I prefer close reading of books and articles, but I know that's hardly a universal approach.