The Feynman technique
Step # 1: Explain a topic, which you want to learn, in plain, simple language to a child. Step # 2: Learn more about what you could not explain well to the child. Step # 3: Improve and simplify your notes / teaching material, so you can explain the topic even better to a child. Repeat.
Sources of inspiration https://collegeinfogeek.com/feynman-technique/ https://www.fs.blog/2012/04/learn-anything-faster-with-the-feynman-technique/ https://mattyford.com/blog/2014/1/23/the-feynman-technique-model https://medium.com/taking-note/learning-from-the-feynman-technique-5373014ad230 https://qz.com/849256/how-to-master-a-new-subject/ https://www.sciencealert.com/3-simple-steps-to-mastering-any-new-subject-Nobel-Prize-winner-Richard-Feynman