This is the Question with a capital Q which everybody asks. Unfortunately, there is no Answer with a capital A. Making money at a casino is a very complex and uncertain task, and if you are gambling with the explicit purpose of making money, you should probably reconsider. Having said that, here are some basics that might help you understand the process better and maybe come out on top.
The house’s edge
All casino games are designed so that the casino’s long-term chances of taking your money exceed your chances of winning money from them. You need to be aware of this principle from the very beginning. It finds a reflection in each individual wager in every game you play. If you are in a game of chance to win, pick the games with the lowest house edge.
Betting systems vs. strategies
Most betting systems exploit the Gambler’s Fallacy, or the conviction that an event that has not occurred for a while is increasingly likely to occur now. Say, you had “red” come up 5 times in a row on roulette, so the sixth time is bound to be black. Wrong. Chance events are not connected, and every dual bet is 50:50. Strategies, on the other hand, are based on studying other players’ behaviour in conjunction with proper math. Learn and use those wisely!