SInce weapon and spell damage scales with your resource, find ways to increase your magicka or stamina pool. Raise your equipment level, use magic or stam enchants on armor and spell or weapon damage enchants on jewelry, Be sure to buff your pool with food. Look at skill passives that increase pool, like Inner Light.

You can also search for specific sets that will improve your raw spell and weapon dmg the easiest to get are crafted ones like julianos or hundings rage. You also have sets like burning spell wave or molag kena that are increasing your base stat by a lot for a short time intervals, also you can find sets like silks of the sun or automaton that are increasing your spell/weapon dmg just for some specific skills.