I think for the examples of skills you mentioned, taking notes would be key. Use one of the tag-based or tree-based note-taking search-friendly apps that often gets mentioned in HN. The act of organizing your thoughts and information in order to take notes would help internalize that skill. In all likelihood you might never look at your notes again, except once or twice, and that's fine - it was worth it from the beginning.

You could even write blog posts about these things you are learning, that would go a step deeper into helping you internalize these skills.