It really depends on the mood I'm in on the day and what I'm playing. If I feel like playing the casino for a bit I might decide how much of my wallet is going in before I stop (maybe 50%) and might decide to stop if I ever get above the starting point from a big win. I definitely think trying to double your money in one session is greedy and destined to fail, so better to avoid that. With sports betting I'll do something similar and maybe spread around a quarter of my balance on a few different bets that look enticing (on horse racing) or one big better on lower value odds like NBA. Superstition doesn't really play any part, but if the mood starts to swing downwards then that is probably a good time to quit.