There is no single strategy that is suitable for all players to bet on roulette. Each player has their own roulette strategy, despite the advantages and disadvantages of each:
The Constant Bet strategy for roulette can be used in all situations, as well as being very flexible it is extremely easy to use, however, it will not bring you big wins. The possibility of winning huge amounts also considerably increases the chances of running out of money prematurely.
The Constant Proportion strategy for roulette is a little more balanced thanks to its self-regulating mechanism of changing the bet size, but it is a little more difficult to use as you need to calculate the appropriate bet amount for each round of play. However, you should be able to do this fairly automatically after a while.
The all-in strategy for roulette has the potential to provide huge winnings but it is also extremely risky, overly volatile and likely to only offer you one or two roulette spins so the playing time is not ideal to say the least.
The Reverse Martingale strategy for roulette is possibly the best strategy of those presented. It has a reasonable playing time, offers a fair chance of winning, and has an acceptable expected value.
The Progressive Bet strategy is also an option to consider, especially for players who may not enjoy the need to bet all the winnings from the previous game, while still maintaining a good chance of a considerable win.
Whichever strategy you choose, keep in mind that roulette is a game with negative expected value for players, meaning you will always lose money in the long run. These strategies are not a miraculous way to remove the house edge, but are rather a way to minimise its effect on your bankroll.