Stick to your profit goal and loss limit. When it comes to roulette and any other gambling game, you should only bet an amount that you know you can afford to lose. Once you've decided how much money you're willing to lose, stick to that amount and don't be tempted to bet any more. Things can get out of hand quickly, especially with a game that goes so fast.
Dear Readers, I have spent many years studying roulette and have tested all the systems covered on this site except the biased wheel systems and the computers. None of the systems I have tested will win long term when played mechanically. Having said that, I do think it is better to use a system rather than just throwing chips on the table. Although, mathematically it probably doesn’t make that much difference. I feel better about my chances when I have a system that I’ve tested and I know what to expect. And that always includes the reality that I will lose on some of my trips. Try to limit your losses and capitalize on your wins. Easier said than done, I know. Maybe even impossible. Never bet more than you can afford to lose and have fun.
Some French tables will employ rules that generally help out the players. The "La Partage" and "En Prison" rules apply to outside even money bets like odds or even, black or red and low or high; they also apply when the ball lands in the zero slot. They are similar in the sense that players only lose half of their bet, but players cannot leave their bet on the table for another spin with the La Partage rule. If a player loses, they can collect half their bet in the En Prison rule, or leave half their bet on the table for the next spin with the La Partage rule.