Instructions
Select a dog from your collection. It doesn't matter which one, although some players speculate that some breeds are luckier than others when it comes to finding items.
Take your selected dog for a walk. The shops sometimes offer polka-dot bows for sale, but for the most part, you must find them while taking your dog out on a walk. This is especially true in earlier games in the Nintendogs series.
Use your stylus to trace a path through as many question marks as you can on your walk route. Some of the question marks are just random encounters with other dogs or objects, but occasionally your dog will come across a mystery gift box that contains an item. Sometimes these boxes will just be lying in the street without question marks to mark them, so it's best to stay alert during walks.
Use your stylus to tug back on your dog's leash when you see a gift box in the street. Gesture toward the left edge of the screen with your stylus to tug on the leash. This will cause your dog to stop, pick the box up and bring it to you. If you're lucky, it could be one of the polka-dot bows.