How did you or anyone else learn to be a mechanic? (...)
usually, here in germany
, in a 3 year lasting apprenticeship
where trained mechanics with journeyman's certificate and master craftsmen explain everything first and then also supervise the work of the apprentice.
should the apprentice make a very bad mistake and damage something beyond recovery, the company / workshop has insurance to pay for the mistake.
(the very best way of learning by doing)
but
if you only try to screw privately, you have to rely on really knowledgeable friends who then explain what, how, where, when to do, and the manual aside
but all that without any insurance
and if then the so called "beginner-in-screwing" makes faults this can be very expensive, that have to be payed by him
what then would be a super hard learning by doing
all alone in my workshop, without much experience i would distance myself from this learning by doing, as it can, depending on what you are working on, very quickly lead to my financial end
not to forget the danger to end 6 feet lower by making faults at a bike that reaches 65 mph in less than 3.5 seconds.
i myself started the screwing 47 years ago, at an age of 16, by pulling the spark´s cap and turn out the spark plug
what a knowing friend told me as a first try to get the "mofa" alive again (2-stroke, 1-cyl., 5hp).