Please note there is a Cookbook available for setting up multi-character support, however this details various aspects:
Under Configuration, Instance there are a few settings that control multi-character support; these should generally be changed at the “Instance” level
Instance.AutoNameCharacter - setting this to false lets people name their charactersInstance.MaxCharacters - how many active characters an avatar may createInstance.CharacterSwitchEnabled - set to true to allow avatars to switch between charactersInstance.AllowSelfRetire - if a character may retire (kill) its self
Note that more interesting setups are possible ; for example CharacterSwitchEnabled can be set to false, and a “zone” created where this value is set to true, this would mean people could only change characters in a specific area (aka an OOC zone)
After this (even if using the cookbook) you should consider adding Characters.Create, Characters.RetireMe and Characters.Select to your instance's menus to allow these features to be accessed. Note you may wish to add “Retire” as a feature that leads to a are you sure yes/no menu, with yes bound to Characters.RetireMe and no bound to GPHUDClient.NoOp. Characters.RetireMe does not ask for any confirmation once invoked.