What are some the more idiotic and stupid mistakes that you know you shouldn't have made but did anyway. Yes this includes other none gambling stuff like sending btc to the wrong address. I'm interested to find out the stupid things other people do. 
Too many people just starts with the martingale, and that is one of the main mistakes that most people do when they start
This is one of the main purposes of why they are losing 10 minutes after starting
Gambling is not easy, of course