To be honest, I only remember 3 pieces of advice my mother gave me before I left home:
1. "Pride goeth before a fall." (don't be too proud).
2. When you go to college, you have to study a little bit every day. You can't catch up at the end of a semester if you don't work steadily along the way.
3. Don't invest anything in the stock market you can't afford to lose.
She was right on 1 & 2; I think she was wrong about #3.