There is no cure for kidney failure (also called renal failure) in dogs. Damaged and diseased kidneys cannot regenerate. The symptoms of kidney failure can be managed; the goal is keeping your dog comfortable and active for as long as possible. A large part of managing kidney failure is feeding a proper diet. While your veterinarian can provide prescription dog food, some dogs don't tolerate it well and may do better on a home-cooked diet. Don't rely on the internet for recipes---find a veterinary nutritionist or holistic vet to help you formulate a recipe for your dog.
Ask your veterinarian for a referral to a veterinary nutritionist. Regard your veterinarian and any other health professionals as part of a team dedicated to keeping your dog healthy and happy. Most vets willingly refer clients to specialists.
Look for a holistic vet who has experience with kidney failure. Holistic vets treat the "whole dog" with complementary medicine and many will help you with a dog food recipe and supplements.
Contact a veterinary college (see the Resources section). Ask if they provide nutritional counselling over the phone---several do, sometimes for little or no charge.
Be prepared to administer intravenous fluids to your dog at home, no matter what sort of diet she is on. It's critically important that a dog in kidney failure get enough water to flush her kidneys. Ask your veterinarian for supplies and instructions on how to do this at home. It may sound intimidating, but it is really not that difficult.
Use the internet wisely. There is a lot of information on dog feeding and recipes for dogs with kidney failure online, but what works for someone else's dog may not work for your dog. Use the internet for research and information, but rely on professionals with hands-on experience for recipes and a supportive diet for your dog.
Home-cooked diets can be made fairly economically and easily by buying and cooking in bulk. Cook enough to last for one or two weeks, and freeze the food in meal-sized containers.
Don't follow a diet or recipe you read about online without consulting with your veterinarian.