Firstly, avoid mixing with other dogs which aren’t your own. Unfortunately, by the time the cough is evident, all of your dogs are likely to have been exposed.
Always consult a vet when you suspect your dog of having kennel cough. In most cases the vet will give the dog something to suppress the cough which reduces further damage to the airway.
Do not take your dog to meet others until it has completely stopped coughing which can be anywhere from five days to a month.