Before exiting the menu, take all of the armor that you just put on off.
Walk out of the house then walk back in, and the armor should still be on the mannequin and you should also have a set in your inventory!
I used Bound Sword while Sneaking and using Healing Hands to heal the Jarl after each hit.
The result was Sneak, One-Handed, Restoration, and Conjuration, all leveled just as fast as when I did it without on my warrior-type.
When you are outside, switch over to destruction magic and use it against that person repeatedly.
This is a little glitch in the game which allows you to duplicated your pieces of armor with the use of mannequins.However, using some of the existing exploits you can craft a set of armour with unlimited enchantments.You are still bound by the number of enchantments you can place on your armor but those enchantments will not have any ceiling.Hit Tilde(~) to bring up the developer console, and enter these codes for the desired effect.Note: certain cheats you can enter a second time to toggle off the effect. Some cheats can cause bugs later on, or cause situations which may "break" certain quests.You can attack the Jarl of Whiterun, and gain infinite xp without any consequences.