My dog went blind a couple of years ago, and here's a brain dump of what I've learned over that time.

It's going to be hard for your dog. She'll likely be sad, maybe even depressed. She won't understand what's going on, or why, only that it's bad. She will need your love and understanding, even when she's doing things that don't seem to make sense, such as running away because she thinks it's caused by you or your home. Having said that, she also is blessed with whiskers as well as hearing and smell that is way better than a humans. Dogs' eyesight is also much worse that humans'. Our vet told us that normal human eyesight is 20/20 and a normal dog's eyesight is 20/100. That means that we can see clearly (read-ably) at 100 feet, a dog has to be 20 feet away to see. Dogs are also red-green colorblind. Having said that, it will still be the loss of an important sense and she'll take time to adjust. She'll bump into things a lot until she learns to be more careful. Pad anything that is sharp and around her height, like corners on coffee tables etc... You can buy corner pads targeted at parents. Keep your home neat and tidy and consistent. She'll learn where everything is and how to navigate by feel over time, but don't make it harder by leaving baskets of washing, bags, shoes etc in the way. Being able to trust her memory from the last time she walked a particular path will help her to adapt. It took about a year for our dog to stop bashing into things. She does this kind of weaving thing with her head now, using her whiskers to feel for obstacles. She also seems to have learned to turn her head at the last moment to avoid a knock while the rest of her body decellerates.

Provide tactile cues for her. I live in a house and we have a different type of doormat outside each door. I also installed 'bump dots' that they use for providing tactile feedback for vision impaired people at the top of our stairs so that she knows before she's about to fall down them. I saw that article about scent training, but to be honest I think it's probably a waste of time. I believe dogs can smell the differences in each room anyway. If you think about it, you probably can smell the difference between your bedroom and your kitchen, and their sense of smell is 25-50 times better than ours.

Start teaching your dog some new commands for while she's on the leash. We use 'step' to indicate that there's a rough patch like a pothole or speed-bump or something like that, as well as 'step-up', 'step-down' and 'bump' for when she's about to walk into something. We use 'free' to tell her that there are no obstacles nearby and she can trot or run safely. She knows them all now, but to be fair doesn't always seem to listen. I've found saying her name first and giving her time to process the implications helps. I might say 'Lucy, step-up' about five feet before reaching a gutter when crossing the road. She'll then do a silly walk until she finds the gutter.

We found she became much less exploratory and adventurous. She used to like to go new places, but now she prefers to walk the same familiar route. That's OK. She also now loves going places where she can just listen and smell to life going on around her, like a dog-friendly coffee shop. I get the feeling that being out in the world is much more exhausting for her. It seems to take so much concentration to walk down a busy street, even on a leash, that she'll sleep all afternoon after an outing.

Start playing games that rely on sound and smell rather than sight. Our dog loves it when we try to creep around her silently and she has to work out where we are. Our goal is to touch her on the flank. Hers is to touch us with her nose. It's like the kids game Murder in the Dark. You can also play this game in an open outdoor area, but running rather than creeping. We also don't throw a stick any more, but rather throw a succession of rocks into the river. She swims towards the sound of the splashes. We also scatter treats on the floor and say 'find-it' to cue her to use her nose to try and find them.

I highly recommend a coat saying that the dog is blind. We humans are a self-entitled bunch and it's amazing how we expect other people's dogs to get out of our way. I had no idea until my dog went blind. A coat makes it clear to others why she just walks into them and people will give her space on the street now. It also cues other dog owners to more closely monitor their dogs behavior. Just be ready for some people to ask 'so is the dog blind, or you?' while you are looking them in the eyes. I've come to see it as a kind of informal intelligence test. :) . You'll also get succession of 'Awww, how cute'. I'm not sure how being disabled is cute, but whatever.

If you have an iPhone I also suggest getting an airtag for your dogs collar. It gives you the comfort to know that if she does get lost you can find her because it's less likely that she'll be able to find her own way home. We've had to use it a few times now.

I don't think it's fair to put the dog down just because they have gone blind. We don't euthanase humans who are disabled, and it's possible for a disabled dog to still lead a full life. It will mean however that you have to accept your new role as a seeing-eye-person.

Good luck!