You Must Reach level 15 or 20 and go into an Oblivion Gate and Reach the Sigil Stone, it should be medium powered stones.
To get the right enchanted Sigil stone, save it before you grab it.
So your aim is to get (shield 25%, reverse attack 25%, fire, water, elemental spell reverse or whatever, aim for reversal stones.
Then do the duplicate cheat on the Sigil stone (this will slow the game down for about a minute if you do not collect all the stones rolling away.
They will go invisible after a while, so probably do it in a room (less furniture the better).
Then enchant 4 items you can equip with clothing, e.g. rings armour etc.
4 x 25% voila! 100% or more shielding, do this with any of the elementals