PermissionEx Bukkit 1.8

Hello i recently bought a mc server and could find any way to get player permission only owner or admin could do /sethome so i looked up for permission and found this plugin permissionex.

The problem is it would not let me create groups or give me permission.
(I am the owner of the server)

even when i do /pex user add it says Error in command syntax.
But in the help menu i could not find anything to help me either
/Promote Doesnt work either so i'm kinda stuck right now. Do you guys what i have to do to get this working?