It is instinctive for dogs to avoid soiling around their sleeping area. When they do need to, they will usually choose somewhere absorbent to soil. However, like with children, accidents do happen.
If your dog is young, unless it is in the yard or an area where it does not matter if it soils, it is best to keep it under constant supervision. Puppies will often want to go to the toilet after food, after a sleep, after play and often during or post any high level of excitement.
Give it as many chances as possible to soil in the appropriate area. For example, when you get home from work, keep a constant eye on your dog, and if you see any signs that your puppy wants to go to the toilet, such as restlessness, squatting or circling, take the dog (without any fuss) to the area you want it to soil. If it does soil in the correct area, remember to give it lots of praise and even treats if you have them available.
If you catch your dog in the act, try to pick it up and take it outside with its head facing the ground so it can see the route with minimal fuss. If your puppy soils in the correct area, again, give lots of praise.
If you find droppings or wet patches or catch your dog in the act, do NOT punish the dog, or rub its nose in it. The dog may not understand why it is being punished, or even worse, just learn to “go” where you can’t see it. When you do have to clean up after your dog, make sure it is thorough and in particular, that no scent is left, (for your own convenience too) but mainly so there are no reminders for the pup about where it did its accident.
Try and teach your puppy to hold its bladder. Pups can hold their bladder for roughly one hour per month of age, so tie them up on a short lead, or put them in a crate or a very small room for the appropriate number of hours. When the time is up, take them to their toilet!
Once you’ve become good at predicting how often and when your puppy will want to toilet, why not put it on cue. To put something on cue we must present the cue before the action to create an association. So if you know your puppy needs to go, say “go to the toilet” then take them outside. Once they go, praise them! Before you know it they’ll be conditioned to go when you tell them to, even if they think they don’t have to go!