Overall, there is no strategy that will accurately predict when a slot machine will pay out. That is the whole point of slot machines. They were created to be random, and to not allow people to know when they will hit.
However, the mechanics of slot machines are often misunderstood, leading to the Gambler's Fallacy. Many people believe that if a machine has not paid out a jackpot in a long time, it is due to hit soon. In reality, each spin of the reels is an independent event, and the odds of winning the jackpot are always the same.