To create a Pokémon tournament, create a tournament bracket in a desired format, as well as the set of competitive rules that all participants must follow for a fair experience. Some resources, such as those found on Smogon.com, explain some competitive tournament rules that are commonly used.
A Pokémon tournament benefits from having access to willing participants, as well as an organizer and a well-written set of rules. Some of the rules involved help keep battles even and fair, and keep battles from seeming too luck-based. Commonly used rules in Wi-Fi battles include the Sleep, Frozen and Item clauses, which limit the number of Pokémon that may be asleep, frozen or holding a given item, respectively.
Pokémon tournaments may be structured strictly, using a list of tiers to decide which Pokémon are valid for use during the tournament. An example of one of these tiers is the Uber tier, which includes Pokémon and strategies considered too powerful for use in other forms of play. OverUsed is the next tier down, which limits as few Pokemon as possible and is determined by the usage of given Pokémon during most matches. OverUsed does not imply the Pokémon allowed in it are ranked in a certain range of power, as this is a subjective category, and instead relies entirely on how popular certain Pokémon and strategies are.