Allow me to clarify...
If you want to have some battles for about 10-20 minutes, use the Quick Battle thread. Post your conditions/rules and friend code, and then wait until someone contacts you via PM/VM.
If you want to have a series of PBR battles with other members for about a week or more, then you can have your own Battle Thread in the Battle Stadium forum.
If you want to host a tournament/gym , then you have to PM any of the Wifi moderators: Horizon, Ursula, or TwilightBlade (me).
Type out a rough draft of the rules/prizes etc of your tournament and PM it to any of the mods mentioned. One of us will decide if it's worthy enough to be posted...