Well, that does sound pretty great, though snakes are not really associated with any one goddess, though you could, say, go with a daughter of Asclepius, god of healing, though the chances of being recognized as such are slim to none. However, it not being a facet of one goddess means you also could wear it along with any other identifying pieces if you went that way. As for shoes, slippers would not be especially out of place, really, or going barefoot, though that will depend on how much you’re comfortable with that/will be going outside.
For ideas on specifics, you could do something like Athena, goddess of battle and wisdom. Find yourself a sword and shield or spear, or do something interesting like a shield on your back and carry around a book. And/or work an owl into your costume (her favorite animal). Or be Iris, a goddess of the sky, with rainbow eyeshadow and nails painted like a sunrise and a vial of water (ostensibly from the river lethe) on a pendant around your neck. Or if you like a gothic look, be Persephone, captured daughter of Demeter, with pale skin and blood red lips (from the juice of the pomegranate). Or be Demeter herself, goddess of the seasons and birth and death. There’s a lot of fun to be had with the goddesses