The best way to increase your odds of winning on a slot machine is to not play. The probability of winning on any spin of the game is set by the game's program, and nothing you can do will affect that. The game is always set so that in the long run the machine will pay out less than what is wagered.
Playing slot machines primarily relies on luck rather than skill. The outcome of each spin is determined by a random number generator, making it difficult to influence the result through skill.