There are 2 kinds of fae: the Nature Fae (also known as Naiads) and the Arcane Fae (also known as Pixies).
The Nature Fae/Naiads are all inextricably tied to an element of nature. The most common elements are Water, Flora, Fauna, Air and Energy (blanket term for fire, lightning and light). The fae draws all of their power from nature, and cannot create something from nothing (though they can make more of something). What element a Naiad is connected to is entirely hereditary, though someone can easily be born with more than one, especially if they're born to two parents of different elements.
Their skin is usually human-colored with patches of unnatural colors (most commonly blue, green or red), though fully-natural or fully-unnatural complexions do happen. Basically all Nature Fae have inhuman physical traits. Such as patches of fur or scales, webbed appendages, plants growing from the skin or hair, glowing skin or eyes, unnaturally-colored blood, etc. Most of them also have different inner workings as well, such as not ( )eathing air, photosynthesis, animal-like senses, etc.
The Arcane Fae/Pixies draw their power from themselves, and all have the ability to alter reality in some way. The most common manifestations of this are psychic powers, creating illusions or constructs, and changing the composition of things. What abilities a Pixie has is not concrete, and one can learn many different ones, although there is a hereditary component as with every skill.
Almost all Arcane Fae are born with unnatural skin colors (most commonly purple, blue or vi( )ant pink), though many choose to magically disguise their skin color or change it permanently. Markings on the skin are common. Not all of them have inhuman physical traits, but many do. Such as extra arms, extra eyes or only one, wings, pointed ears, non-furry tails, etc.