Some infectious coughs are self-limiting and resolve within a week, however, they tend to get worse during that time and can be quite stressful for the dog (and owner who isn’t getting much sleep because of it!).
In most cases, it’s best to have your dog seen by a vet rather than attempt home-remedies, since your vet will properly diagnose the underlying cause of the cough. Some vets will prescribe over-the-counter cough medicines for kennel cough, but it’s something that should be discussed with your vet as not all dogs can tolerate these medications.
Trying a spoonful of honey for its soothing properties and “steam therapy” (putting your dog in a steamy bathroom to loosen up their chest phlegm) can help soothe an annoying cough. Ensuring they have a good plane of nutrition (a good balanced dog food), access to fresh water and plenty of rest also helps speed up recovery.
Isolating your dog from other dogs while the cough is present is also an important infection control measure.