Key supplies for a successful dog park visit include water to keep your furry friend hydrated, collapsible dishes for convenient drinking, and waste bags to clean up after your pet. Additionally, bring along any necessary medications, like flea and tick prevention, and ensure your dog wears ID tags and is microchipped for added safety. Avoid bringing food with strong scents to prevent attracting unwanted attention from other dogs. These supplies will help ensure a safe and enjoyable outing for both you and your canine companion.