Online casinos are built to bring in a fortune to their owners. If you want to know how to avoid that, my answer is you can not. But there is a way to earn thousands from them.
At current times most online casinos offer first deposit bonuses. E.g. if you deposit $300 you get a 100% of welcoming bonus. Which means you will get another 300 dollars from the casino. tebak dadu Now you need a strategy to play through the money and lose as little as possible. I say lose, because the casinos are built in a way that they will win more in the long run. This is why you need to pick a strategy.
I personally recommend using the blackjack strategy card. Using this you will win 46% of the time and the casino will do so 54%. This may vary as you know depending on your luck. You might win more or less. In the long run, those should be the percentages that will come out.
My point is that you should take the money that you deposited and received as a bonus and play blackjack as long as the money is played through and you can withdraw it. In my example you deposited $300 got another $300. Now you played with the money and lost a little to get it open to withdraw it back to your bank account. After playing it through you should still have $550 which is $250 earnings for you. Now you can take the 550 and deposit it to another casino and earn more. I started with $200 and came out with 2300 dollars.