How old is he?
How long is he doing this?
Is he able to urinate?
Is he eating?
If he coughs every day like that he may have an allergy to food litter, products, etc. He could have slight asthma or even a cardiac issue.Or a bad tooth.
Coughing is very concerning in a cat. Much more so than sneezing, which usually indicates an upper respiratory infection.
If he is eating food with corn or gluten, try a more natural grainless diet http://www.petfooddirect.com/ for choices.
If he gets hairballs put remedy or vaseline on his paw daily for him to lick off.
Some cats do make cooing or singing noises before they cough or throw up.
You do need to have him evaluated by a vet to find the cause of the coughing.
Please let me know how your boy is doing. I will always be here for both of you.
Sincerest best wishes,