There are two main worst roulette strategies to avoid: the 666 strategy, and studying for patterns.
The 666 system is an aggressive strategy that involves betting on as many numbers as possible at once. The theory is that the more numbers a player bets on, the more chance there is to win. The strategy is called ‘666’ since all the numbers on the roulette wheel add up to 666. Usually, the players lose when choosing this system, so it cannot be called one of the best roulette strategies.
Studying patterns in roulette is useless since all online casinos use random number generators. Therefore, the outcome of each spin can never be predetermined.