Started investing since 2009.

Lesson learnt: Best time to start is after a recession.

Lost about EUR2k trying to understand forex derivatives.

Lesson learnt: Not for mortals. Will not touch ever again.

Got some stocks in the red, but fortunately overall up cos of portfolio diversification. Worst performer -44% (LPKF). Best performer +511% (MSFT). Lucky enough to have made more hits than misses. My holding period is very long. I've held MSFT for 10 years.

Lesson learnt: Diversify, won't be super rich, but will let you sleep at night.