Find something that works for your head and face - that's number one. Ray-Ban is the best brand, in my opinion, because they have lots of different shapes, they fit well, last a long time and are... more
Keep it super super simple! I generally don't like rings at all unless it's a simple band. No necklaces, either. Bracelets are the best bet - metallic is best, dark wood could work, too.
Dark or light is best (Like the Kenneth Cole or Inhabit scarves). Most of the time brown or plaid patterns look too much like "old man by the fireplace" to me.