I'm an old timer. My coaches were 40 year-old WW2 veterans who smoked a lot (everybody smoked, even us 12 year olds every chance we got.)
The only instruction I can remember is, "You've got to stride long to hit long." Like Mickey Mantle, I guess.
Of course I learned to play baseball on the sandlot. It was a real sandlot-- an abandoned gravel pit.
My first real job at age 16 was being a surveyor's assistant. They sent us out to survey the gravel pit so it could be turned into condominiums. Uggh.
FWIW, that was the first time I'd ever heard the word "condominiums."