Pachinko (0000) is a mechanical game originating in Japan that is used as an arcade game, and much more frequently for gambling. Pachinko fills a niche in Japanese gambling comparable to that of the slot machine in the West as a form of low-stakes, low-strategy gambling.
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.