There are several misconceptions about slots that merit clearing up.
One common belief is that a slot machine that has recently given a big payout will not do so again for a while. Statistically speaking, however, the odds are the same for every spin and every spin is completely random and exclusive of all previous spins. So there's no way to predict the next spin and a jackpot is just as likely to be hit right after the last one was hit or after a thousand dry spins.
Another misconception is that slots run in pay and take cycles. Actually, however, modern slot machines generate random numbers which take seed values from variables presented at the time of the spin. Thus, pay and take cycles are truly pure myth.
People believe that if you walk away from a machine and soon after you see someone else winning the jackpot on it, you feel that had you stuck on a little longer, you would have been the one to win. The truth is that you would have had to spin at the exact same microsecond as the other winner for the jackpot combination to have been set.
It is also a popular misconception that slot machines stop on any possible set of symbols with equal probability. The truth is, as the random numbers are mapped into positions, certain positions are weighed by the machine to more likely be mapped to than others. Modern slot machines simply weigh the probability of a specific outcome such that jackpots are hit a specific percentage of the time and thus we have predefined payout rates.
You can go through some of the online slot machine myths for gaining more tips on slots