The Saturday Evening Post reprinted a 1939 article on the greatness of Edgar Rice Burroughs, the creator of Tarzan. Some salient points on "literary training":
>Be a disappointed man
>Achieve no success at anything you touch
>Lead an unbearably drab and uninteresting life
>Hate civilization
>Learn no grammar
>Read little
>Write nothing
>Have an ordinary mind and commonplace tastes, approximating those of the great reading public
>Avoid subjects that you know about
The article is extensive, but you can read more here:
https://www.saturdayeveningpost.com/2018/11/how-to-become-a-great-writer/