Firstly , this is working only on high-rates (i mean it's working on low's also , but useless -> you'll see why)
So , let's get started .
Everything is simple , the first thing you gotta do is add a sub-class (paladin per example) . Now , get on the main and then back to the sub you've added(paladin)(if you don't do this you can't cancel ur subclass - "There are no subclasses available at this time") . After getting back on the sub(paladin) , use the buff you want to "stuck" (Majesty , deflect arrow) and cancel sub , then add the class you want to play with (Hawkeye per example) .
You all know that when you cancel a sub , while ur on that sub , the buffs will transfer to the second sub .
Now , you have majesty+deflect arrow on HE :-) GF ?! :P