Gods, in their natural state, are beautiful, divine, mighty, powerful, elemental, titanic, immense, glorious beings that a human would not dare look upon, less they burst into flames.
Gods can easly shift between their divine form and their human disguise whenever they choose. When a god reverts to his/her divine form, they become radiant with light based on the color of what they embody. If a god feels strong emotions (particularly anger), they will uncontrollably revert into their divine form unless they regain control of themselves.
Demigods (because they are born of the divine form) are able to see the smallest bit of a god's divine form by looking into their eyes, they will also see events caused by the god. It is unknown as to what extent they can behold the divine form however, because they are half-human, they cannot behold the full glory of the divine form without burning up.