Witchcraft

"The boundless magic of the depths...that is what the krakens have taught me. Fish stuff mostly." - Gertrude Müller, Sea Witch

Perception is indistinguishable from being. What a thing, or a person, is seen as is often as important as what it actually is, if not more so.

Witchcraft is the utilization of this fact in both its smallest and grandest scales. Wizards catalog and use the magical virtues of concepts in the world in poetic or literary forms, using rhetoric to shape the aether into spells. Witches by contrast take advantage of the myriad ways that magic shapes itself, or that people shape magic without knowing it, or that magic is shaped into people - an often subtler and more complex way of exerting will than the ordering the universe around that wizards pride themselves on.
On a simple level, witches engage in the same basic "rituals" as everyone else. They wear certain clothing, to be seen in a certain way. They choose their words and behaviors for effect. All the world is a stage, and witches are particularly self-aware about being players. In this way, because everyone knows that pointed hats and robes mean magic, a mage who dresses the part can expect their command of aether to be bolstered by this known fact. All mages do it, but witches take this further.
Incarnations are beings composed of magical virtues. Where a humanoid mage might invoke the virtues of fire to cast a flame spell, a dragon or ifreet can simply call upon their own firey natures. Witches can imitate this. By acting the part, emotionally, spiritually, and sometimes physically aligning themselves with an incarnation of choice, they can imitate the way in which an incarnation's spirit naturally imposes itself on aether. Unlike a dragon sorcerer, who will use the blood or bone of dragons to create implements or modify their body, a dragon witch's changes are internal, speaking like a dragon, thinking like a dragon, embodying draconic wrath or wisdom or greed in a bid to claim their power.
Witches often must study with the entities they wish to emulate. A popular negative stereotype of the witch is one who has turned to fiends to learn their ways, steeping herself in their evil in order to cast diabolical spells. There is some truth to this, as it is a quick way to power, and witches who entreat demons, dragons, or the fae for assistance often find themselves serving as the emissaries or servants of such creatures. However, many witches learn their ways not directly from incarnations but from generational apprenticeships that place the original act of consorting some centuries back.
Even a witch who has never met the incarnation they take as model will inherit some of the disposition of the creature. Witches are at their most powerful displaying tokens of their allegiance, learning the customs, and indulging in the vices of their incarnation of choice. Some struggle with their role as magical method actors, their personalities torn between their witch persona and their natural inclinations. Others revel in the masquerade, slipping in and out of the role or giving themselves over to it.