Using the KONG Wobbler is easy. First, unscrew it and fill it with your dog's favorite treats or food. Then, screw it back together and give it to your dog. Your dog will nudge it with their paw or nose, and as it wobbles, spins, and rolls, treats will come out. You can use it as a regular toy or as an alternative to a dog bowl during mealtime. When it comes to maintenance, it's dishwasher - safe, but you can also unscrew it and clean it by hand easily. Always supervise your dog when they're using the toy. Make sure to remove all the packaging before giving it to your dog. If you notice any damage, stop using the toy right away. For size selection, if your dog weighs up to 25 lb (12 kg), choose the small size. For dogs over 25 lb (12 kg), the large size is more suitable.