I know two people who taught themselves how to hover a helicopter. Both still alive and none the worse for the experience. Both learned on Rotorways.
Evidently Rotorway used to produce a book on how to do it (I'd gladly pay for a copy of that if anyone has it!!).
Long involved process, but one of the aforementioned pilots said that after the process he decided to take a lesson in an R-22 and amazed the instructor by being able to hover very accurately within seconds of taking the controls.