Getting a blind dog to go down steps?

I have a dog that is 15 years old and he is blind from cataracts (probably caused by the diabetes he has.) In the house i live in, there are a lot of steps unfortunately and lately he has been afraid to go down the steps in the backyard (there are only 3 of them.) He usually will step on one and jump over the other ones so lately i have been picking him and then putting him down gently in the backyard, but he hates being picked up. Is there a good way to train him to go down the stairs one by one or should I get a ramp?