Setting Guild Title - Newbie Here

-Hello, hopefully, someone might help me, Yesterday I created my guild, afterwards, i invited players to join my newly created guild.
-I was hoping the guild set-up is just as easy as i thought it would be. But to my surprise, to me setting up the guild in-game turned out so much complicated to me being a newbie.
-So i googled and luckily found post on youtube on setting the legion. Ok fine for me.
-But I am STUCKED on HOW TO ASSIGN GUILD POSITION/TITLE to my guild members. I cannot assign titles like, commander nor veteran to any of my selected member, AS OF THIS WRITING, All my members are soldiers.
-I have searched/googled AND UNLUCKY TO FIND ANY INSTRUCTIONS which ROHAN should have done.
-thanks for any information or guide that i can follow.
-Big thanks.

Form a legion tab. Then delegate authority tab.