need help with group manager plugin

i really need help with my essentials group mnager pluging for my bukkit server because quite frankly i dont know how to use it it wont let me promote me or even put me in a rank/group iv been getting really annoyed with it because i want to be put in the owner group on my own server i aslo would like to add my friend but it wont let me do that either so if somebody could please just put the command player group thing int an example instead of /<command> <player> <group>





im putting this thing into the prompt and it is saying unknown command

/manuadd theepiiicnoob owner