how to use the super backpack?
another way to say this is how to equip it?
You need a ‘back’ item.
Easiest way for you is to complete a lvl33 Personal Story mission and you can use the backpack on it.
You can get one by completing personal story as GuzziHero mentions or purchase one at BLTC.
You are looking for Ghostly Spineguard. lvl35 required to use it tho. When you get it, its just to transmute as with other items.
As the others mentioned above me.
You can find your backslot where you can equip rings, accessories and stuff.
Back items are available from lv 33 and so on, you will have to level up a bit more, to use the skin an a back slot item:)
Also: Back slot items can sometimes be obtained from Holiday events too. Maybe the next installment of the Flame and Frost living story will award you with one.
thank you so so much, guys!!