Stay away from high oxalate foods: some are beets, spinach, rhubarb, strawberries, nuts, chocolate, tea, wheat bran, and all dry beans (fresh, canned, or cooked), excluding lima and green beans.
It is best to avoid these foods. Also limit salt and limit animal protein
. Taking in high amounts of lemonade or lemon extract from ReaLemon 4 tablespoons per day will help tremendously.