First way to start, is take your kids to Target and walk them through the halloween aisles. Let them find the clearance dog costumes. Say no twice, then start laughing at the costumes and buy 3 for your dogs.
Second, is to set up the camera to take photos
Third, dress them up and make them pose for photos while dressed up. This is good for a good, eye watering laugh. Not sure the dogs are quite as amused