Biggest Errors This Year (So far)

1. AAPL Options - got the direction right (roughly) but didn't figure on the loss in implied volatility after earnings. I bought August and October calls at 256 and 260 the day after very impressive earnings (August 20th or so) and sold at 263-264 about a week later, but for a big loss. The loss was mostly because of the huge loss in implied volatility in my August calls.

2. Silver futures - Position size too large. I was trying to make a quick buck, catching a falling knife with futures. My position size was too large and so I couldn't think clearly in the face of losses. I panicked and sold for a loss. This happened two or three times I think.