However, most skills must be used in combat in order to gain the increase. Conjuration increases a little bit each time the Dragonborn summons a Bound Weapon or creature, for example an Atronach. The level of a given skill is increased as the skill is used successfully - Archery is increased when an arrow hits its target Destruction is increased when a spell causes damage to the target Sneak increases when the Dragonborn remains undetected in Sneak mode while in range of NPCs who otherwise could detect them, etc.