You first need to create an account at a licensed online casino. Then, deposit funds to your account through an accepted payment method. Choose the slots game you want to play, start it up, and set the size of the bet. Now, you just have to press the spin button to play one round.
The random number generator is an algorithm generated by a computer that online casinos use to randomize the results of a spin. It does this by generating a sequence of numbers, each number corresponding to a symbol on the reels, which one cannot predict by any means other than by chance.