Your resin jewelry is best stored on its own and out of direct sunlight, as sunlight can yellow resin over time.
Be sure to remove your ring when using soap, detergents, etc., as they may affect the surface of the resin. If your resin ring becomes dull, a soft damp cloth followed by a dry cloth will usually be enough to make it shiny again.
You can also use a tiny bit of coconut oil and rub it on to make the surface shiny.