In order to use this mod in game, like on a minecraft server, the mod MUST be on the client and the server in order to function.
In order to access the customization menu press F12 or go into your inventory and press the icon next to your character.
This mod allows people to either create custom character models or use presets like the protogens included in this mod.
This mod is in essence, a copy of the More Player Models mod just with Protogens as base characters aswell.