What's the biggest mistake you've made while trading?

$FOMO ETF (FOMO.US)$ All my losses are from FOMO. You know it's stupid and you say you won't do it, but you do it.

Trades that made me money are when I have a clear picture in my head of what's going on in the market and make a couple of bets.

Like Thursday I thought banks would sell off Friday and bought puts. Saw calls go to 1000%. Unfortunately it was a weekly so I didn't put a lot in it. Ended up selling at 400%

But don't worry my yolos made up for it and I lost 2k