Interestingly, I know someone who recovered from a concussion (it took her over a year for her symptoms to go away completely, although she went back to work after a couple of months). One thing that seemed to help her was simply resting in the sun with her eyes closed.

I've started doing some short walks outside (combined sun/shade) again and it seems to help with my overall sense of well-being. Still, my advice would be to resume activities, including walking outdoors, slowly and cautiously.

Personally (as someone who is improving but is not out of the woods yet), I don't think there is one cure-all for PCS. I think the best strategy is tons of physical and mental rest as your foundation (especially early on), combined with other approaches, such as good nutrition, vitamin and/or fish oil supplements, psychosocial support, meditation and/or other relaxation techniques, gentle activity/exercise, etc. Each person has to figure out what works best for him/her.