I learned frugality up close and personal from my parents. Growing up as one of 7 kids in a immigrant, minority family, and living my early years in one of the most dangerous sections of New York (though we kids did not know it at the time), I (and my siblings) saw my parents practice frugality. They were not ashamed of it, and didn't not make it seem like a burden.
The other import ant lesson was self-sufficiency. I never heard my parents`complain to us about life being unfair or discrimination - instead the emphasis was on personal responsibility, no job was beneath doing, and making the most out of ones skills.
Many of their adult friends, some of whom I viewed as mentors, had the same attitude. I can't recall any of my parents close friends being wasteful or extravagant - though we saw a lot of that in our neighborhoods. They would also encourage us to have friends who had goals - the adage "show me your friends and I'll show you your future" was something they taught us growing up - and which we experienced its truth.
The investing I learned primarily from listening to and observing older workers when I joined Megacorp. The main lesson was to not fall into the get-rich-quick mentality, but focus on the adage "slow and steady wins the race" when it comes to personal finance. I built on this by reading Money Magazine and personal finance books from various proven authors who emphasized that latter view. Of course I made mistakes, but fortunately they were relatively little ones.