It is highly recommended that you DO NOT FILE A CLAIM by yourself, it is highly recommended that you use the FREE talents and knowledge of a Trained, Certified Veteran Service Officer.
Every VA medical facility has National Service Officers on duty; most states or counties have local State or County Veteran Service Officers on duty that stand ready to assist you in your claim filing, follow up and appeals. You do not need to pay someone to file your claim. Also hiring an attorney does not guarantee a successful outcome.
How to find a Certified County Officer: http://www.nacvso.org/find-a-service-officer
How to find an Ohio County Veteran Service Officer: In Ohio dial 1-877-OHIO-VET (1-877-644-6838).