If she's living with you, tell her to get used to the layout. We moved last year and it took me about a week and now I can navigate the house in pitch-black darkness with nary a problem (legally blind from birth.)

As for what you yourself can do, make sure everything is in its place and she knows where everything's place is supposed to be and be on top of that shit. Keep an organized house for her to memorize and she'll be fine in a week if that.

Maaaybe get her an O&M class but if she won't use a cane, I doubt you'll get far with that. Maybe a youtube video would work better. Good luck.

I’m blind in one eye and low vision in my good eye. One thing that helps is I got rid of all glass wear! I have really bad depth perception so I knock over cups a lot more then I want. So I also have cups with lids. I’m use to the layout of my home so I can walk around in the dark with no issue but she has to try to learn that.

Could get some textured rugs or mats to put on the floor near them as a warning indicator. Could also put some like a strip of crinkly sounding stuff on the bottom so it also makes a sound, but becarful to not put to much and make it slippery. I guess you could like put on nonslip stuffs over that too if you really needed to. Theres probably some kinda lazer sensors or movement sensors out there you could hook up to sound emitters to make a noise when ever somebody goes near the stairs too. As fair as other hazards go, should probably make sure there's no sharp edges she could easily scrape or hit around the house. I hate it when our crappy armchair cuts my leg or when my hip gets attacked by the microwave table cuz I'm not paying attention like I should.

I have RP and am almost completely blind when it gets darker, so we bought several Alexa devices and Hue lights for nearly every room.

Now if I walk around at night, I don't have to 'search' for the light switches, I just activate the light with alexa.

Even if your gran isn't ready to face up to what adaptations could be made (that would probably assist her a lot) , you could seek advice from your local charity that supports visually impaired people or similar service in your area. They can give you really good advice on what products and services (both everyday and specialist) will be really helpful.

Even if the vision in her other eye is relatively good, her depth perception will almost certainly be affected, making stairs and other trip hazards a particular risk. Small changes like effective colour contrasts, rug grip tape as mentioned and extra tactile input (a raised mark or even elastic band to indicate the start or end of a rail or a change) might be useful.

The people at the organisation can advise you on how to broach the conversations with her, so shoe doesn't feel challenged or talked down to (not that's what you are doing, I know), so hopefully for now, she can appreciate that making a few small changes can do a lot to ensure her safety and wellbeing.

Get her involved in arranging everything exactly as she wants it and reassure her, anyone visiting will not move anything without returning it to its rightful place.

It is not about spending money on gadgets at this point that she will probably reject, as she is clearly still trying to come to terms with the loss of sight in her eye (and quite understandably probably worrying greatly about what might happen should the other deteriorate).

Therefore you need to tread very gently- just encourage her to open up about what "little" difficulties she has been experiencing and asking what she thinks might help, then input any suggestions you've been given.

I've both worked for a visually impaired charity and cared for an extremely er "single-minded" gentleman, so I can really empathise with your situation.