First and foremost, keep a record of your games best online casino sites would do it for you, but you might be more comfortable with plain pen and paper. The record is not just about analysis and analytical value it will also help you see the general patterns so that you can recognize whether your day is going to be lucky or not. Luck is very important in a chaos system games such as roulette. If your guts are telling you this is going to be a bad day, quit. Do not use casino supplied pads with numbers that you can cross or write off. They only encourage you to bet on the numbers that didn't come out yet, and this is a very bad idea.
Doing so drastically amplifies the house's advantage. As roulette is a game of fixed odds, the house edge on every bet is fixed as well. Unlike in Blackjack, you can’t manipulate odds and house edge in Roulette. Any system that claims to do that is obviously lying. Avoid those at all costs! Remember that American 5% is a very high house edge, so if at all possible play the European wheel instead. The only irregular bet in American roulette is the five bet, and since it has a significantly larger house edge, you should never bet on it because it's simply counterproductive.
Look for wheels or real money slots with surrender traditionally Atlantic City/American wheels and en prison traditionally European rules. They drastically reduce the house edge. Contrary to a popular myth, the outcomes of a roulette round don't depend on each other unless there's a physical bias of the wheel which is most unlikely in real life casino environment and technically impossible in online casinos, so any system that depends or claims to depend on a prediction of next result cannot work with roulette. Some go as far as claiming that there is an actual statistical relationship between any number of throws of a ball, and that if, for instance, you get zero twice in a row on an American wheel 1/38^2, the probability of the third throw also playing out zero would be 1/38^3, or 1/54872.
Therefore, they wrongfully deduce, once you actually get zero twice in a row, the third time you play a ball the probability of playing zero again would be 1/54872. Based on this, they would then conclude that any throw is directly affected by outcomes of previous throws. This is a mathematically absurd statement because roulette throws are physically independent from each other and the probability of next throw resulting in zero again in the above example would always stay 1/38. The fallacy is easily debunked as soon as you consider the probability of two zeros occurring one after another before your experiment. The wheel does not have memory, and any assumption that latter throws are somehow dependent on the former ones is false. Avoid use of martingale like systems which are known to be unstable, risky and dangerous in the long run. You can combine it with another betting system or use tactically on short streaks here and there, but not more than this. Martingale systems are not suited for real life casino situations and will ruin your wins.
Roulette is a thrilling game. When you play Roulette, it is especially important to know when to stop, both when you lose and when you win. By all means, limit your losses. Most inexperienced players would just bet randomly and repeat on and on. This is not the right way to play roulette just throwing money around doesn't help, and if you're gravely mistaken if you think you should play as long as you wish. Controlled betting is the way to go. The key to leaving a roulette table with profit is when you have profit in your hands and not a second later. Many players who know that will usually set up a daily spending fund. Whenever they win anything, they will put the win aside and not wager it again. On a lucky day, when wins will reach a certain limit that the player considers for themselves, they would stop playing. This technique is called bankroll management.