One of our dogs went blind, but she was under 10# so we could just carry her up and down steps. She could see light/dark shadows at first, so could avoid large objects in her way. She walked on a leash , but we walked her in an area she knew. Before total blindness, she used her nose to find the edge of a step to know where to start going down. After awhile she could no longer see to judge distance to jump, so we would lift her on and off the sofa also. She always found a way to communicate what she wanted and we just helped. She died at age 16 a couple of years ago and we still miss her even though it was a lot of work.