In order to have access to the Mog Locker you have to have access to Whitegate. I will paste two links below that will explain what you need to do to open up the lockers and expand them. Basically you will have to become a member of Whitegate's "military" and will have to do a "Staging Point" run to become part of the military and be granted access to the Mog Locker.
A little advice, when you chose which Staging Point to do, the easiest one is the Halvung Point. I have taken my level 1 Mules thru this run with no deaths. Must importing thing YOU will need is Sneak/Inv meds and the ability to use the spell ESCAPE. Having ESCAPE is what makes this the easiest point out of all of them. Good luck and have fun. There are some nasty mobs along this route, bombs for one, but it's doable.... Skyfiredancer (talk) 18:43, July 5, 2015 (UTC)