Ask HN: Best resources on learning to be a better teacher or mentor?

I'm a ~senior engineer, worked for a handful of startups and larger companies. Mentorship and training is an area of work that I really want to explore, but I don't think it's my strongest skill right now. How can I improve?

Some people seem to have a natural ability to break complex topics down into comprehensible pieces. That's something I'd love to learn more thoroughly.