I have mild bilateral knee osteoarthritis and am not being treating for it and would like to know what to do?

The doctor that diagnosed me I saw for something else and through x-rays from were I had pain came up with this also. I am no longer seeing this doctor since the problem I went for has been taken care of. Are there any natural things that I can take that will help? And what types of exercises are best. My right knee is really bothering me, my left is fine. Please help.