To build skill of action or thought, don’t focus exclusively on the skill. Explore variations and intersections with other skills.
I just started on David Epstein’s book Range: Why Generalists Triumph in a Specialized World. He starts out with a comparison of Roger Federer (early “generalist”, non-driven approach to sports) with Tiger Woods (prodigy, parentally driven).
It reminded me of an idea I read in Make It Stick: The Science of Successful Learning (nice summary here, interesting-looking podcast episode here) several years ago. That is: if you want to build skill, mix up your practice. To get really good at one particular thing, practice a lot of variations around it, let it marinate in your mind, do other things “further afield” to distract your conscious mind. The book gives an example of a study in which kids practiced throwing bean bags into baskets at various distances. Some practiced with a single target distance, while others practiced at other distances, but not at the target distance. Ultimately, the “varied practicers” were more skilled at the “target distance”, and presumably at other distances as well.
“Learn all the skills, but learn them slant.”
Known Unknowns 