This requires that you can summon a Frost Atronach.

First summon the Atronach and then take out any weapon you want to use, or the armor you want to equip.

Then constantly attack the Atronach until it either dies or runs out of time.

This should give experience to whatever type of weapon you wield.

Repeat this until you are the level needed in that category.

P.S. If destruction spells are used on the Atronach, the Atronach will attack, but this is where the armor leveling comes in, so make sure you bring healing potions with you or just run into a pond specific area to go to Morthal.

Constantly continue to do so until the required level is of your liking.