Hello! My Ray C. is blind, but the great people here really helped me out when it came to finding out how to properly care for him. Here are some tips they gave me:
-Use a feeding ring. Since it keeps all the food in one place, it'll be easier for you new betta buddy to find it (once he realizes what it's for.) Also, try to keep a consistent feeding schedule.
-Never move anything! Once you have introduced him to his new home and he becomes familiar, he'll become active and happy. However, when you go to clean the tank out, be sure to arrange everything as it was before, because if stuff is in different places, he'll get confused.
-Try to avoid the usage of gravel. You can use it, but the reason why they recommended that I try not to is cause it makes it easier for the betta to forage for any fallen food. Another reason why is........
-Because you should definitely try to avoid anything not smooth or soft. Because blind bettas mostly get around by touch, why not make it easier on him by getting silk plants? They already recommend silk or real for regular bettas, but even smooth-rounded plastic plants will work so long as they don't snag on anything (you know, the pantyhose test.)
I think that's about it! I found that these tips have really helped Ray C., who is a happy, healthy (least of all, vision impaired) betta. Of course, if you have any more questions, all the other lovely people here can be of more use than I.