Your cat cannot explain his symptoms, so it's the responsibility of you and your veterinarian to take care of him. You can help speed the diagnosis and recovery by having the answers to the following questions ready.
Start by having the answer to some general questions.
After answering some general questions, more specific questions need to be answered.
Regarding the eyes:
Regarding the ears:
Regarding the nose:
Regarding the mouth:
Regarding the chest:
Regarding the abdomen/stomach area:
Regarding the urinary and reproductive systems:
Regarding the musculoskeletal system - bones and joints:
By being able to answer these questions, your veterinarian will be in a much better position to help your pet. Additional tests may be necessary to find out what the problem is but the answers to the above questions can greatly narrow the area of concern.