Always send any mail to the VA certified mail and keep the green tab that they have to send back to you.
If you do not hear from the VA within two months of sending your claim then resend the claim certified mail again, with a copy of the original claim.
In your claim, describe all symptoms that you believe related to disorder (i.e. I hurt my right knee in servie but my left knee hurts now too because I’ve overused it or I have a service connected back condition and I am now suffering from a mental condition because of the limitations that my back puts on my ability to do what I used to do).
List where you are treating and where you have treated for you condtion.
If you are sent to a VA medical exam for your condition take a spouse or someone you trust along with you. After the exam that person should write out a statement of what he observed.