Go to your forum, scroll down to the end of the page and click Go to Administration Panel
.On the side menu scroll down untill you see the "User Admin" section. Under that click "Permissions", after that enter the username you wish to assign Mod/Admin rights to. Press Find Member, then there should be something like this.

Username: Maki

User Level : Here you can choose between User/Administrator

Usergroup memberships : None

Under that, you can assign particular forums to a user to moderatore, thus making him moderator....