[anonymously]

Feed him measured amounts twice a day, add a little water to his food. I would use a high quality kibble as a base, a tablespoon or two of wet food or cooked chopped chicken or lean meat added.

Some tips here under general guidelines http://www.homeovet.net/dynamic/php/downloads/dog-c8470f2c75dbe4b683205c3919ee2310/dog_diet_complete.pdf

PS: Poor appetite and changes in appetite could be a red flag that something is wrong, if it continues more than 72 hours call your vet for advise.