Ron Miller is an artist who made some very nice visualizations. I can’t vouch for the scientific accuracy, but they seem plausible enough to me, and consistent with the images I’ve seen of Saturn’s rings from nearby probes.
Off the top of my head, if the rings were a narrow band around the Earth, and were aligned with the terrestrial equator, they would be less visible from high or low latitudes. If they were aligned with the plane of the ecliptic, then they would be visible as a band following the 'zodiac constellations', and thus visible much further North and South.
At night, in the shadow of the Earth, I'd think that they would be dark, perhaps even invisible. Perhaps moonlight would serve to illuminate them, depending on the relative position of the Sun and Moon.
I'd guess they would look most impressive around and dusk. The particle density and albedo would influence whether they would be visible during full daylight. The ring density would affect whether they had sharp edges or simply faded out away from the centre.
