PvP Tournaments are a series of matches in which someone in human form stays in a place where there are a number of Red Soap Signs placed or the invasion rate is high.
Setting Up PvP Matches
If you want to host a tournament, you will simply need to reverse hollowing and go to an area where you can be invaded as well as summon people via Red Soap Sign and either let them duel or or wait for one of them to fight the remaining Red Spirit.
Setting Up Rules
If you want to set up rules simply message the Red Spirit that was summoned or has invaded you and tell them rules that you would like them to follow.
Watching The Duels
If you were to host in the Undead Burg you would want to stand in the area where the Undead Soldier who wields the cross bow is or stand by where the Undead Spear-men are.