I made a slew of how-to videos during my time as Digital Editor at Making Music Magazine from 2012-13. Here's my favorite, in which I demonstrate how to improvise a decent jazz piano solo without devoting years of your life to music theory. It's some of my earliest animation work, a little rough around the edges, but still managed to get 2.5 million views and nice feedback :D
The technique presented in this video is not to be found in any lesson book or taught by any music teacher I'm aware of. It's sort of my own 'hack' to soloing. I love taking complex concepts, like jazz improvisation, and boiling them down to their simplest, least intimidating techniques.