1) Try to play the European variant of roulette as often as possible and since every online casino worth their salt offers both European and American roulette, this should not be a problem. The house edge in European roulette is roughly 2.7% while the house edge in American roulette is more than twice that amount.
2) Betting on single numbers is actually probably the worse thing you can do. It is the roulette version of betting on proposition bets in craps and it is a big sucker bet that you should try to avoid.
3) Do not chase your losses! This is a big tip that you need to keep in mind. Chasing your losses will only increase the edge of the house and ensure that you end up going home a lot sooner than you would probably like.
4) Parlaying bets is also not a good idea. A parlay is when you take the winnings that you get from a specific spin of the wheel and put them along with your original bet back out for another bet. While it can have the advantage of increasing your profits quickly, you need to hit a streak of luck in order for it to work. Whenever you are relying on luck for victory, remember that the house edge rules all.
5) Putting aside your winnings after you get them is a good idea, because it can give you a psychological advantage that is often very important in online gambling.
6) Roulette is a game of chance and for that reason there is no single strategy that will work in beating it. Any strategy is pretty much as good as any other once you have minimized the house edge, so keep that in mind before you end up falling in love with a strategy that will only hurt you in the long run.
7) Make sure that you bet with a budget. This one should be pretty self-explanatory by now.
8) In American roulette, try to avoid the bet that covers 0, 00, 1, 2 and 3. This bet carries a very high house edge.
9) If you can actually play French roulette you will find that it is even better than European roulette because the la partage rule in the French variant of the game reduces the house edge to below 2%.
10) If you are playing at a land-based casino, be sure to keep an eye out for the dealer signature. Some dealers that are inexperienced or tired will spin the ball in a way that allows it to land in the same region of the wheel each time.