Modern gaming machines use computer technology to operate their functions. Slot machine outcomes are determined unsing a Random Number Generator (RNG) which is a mathematically-based program that selects groups of numbers to determine which symbols are selected to produce a winning or losing outcome.
The truth is that there is no trick to slot machines. They provide random results based on set mechanics and it all comes down to luck. With that being said, not all games are the same, so picking the right options is key, and you can still change the size of the bet throughout the session for better results.