Although many believe that housetraining an adult dog is nearly impossible, it is absolutely not, and with the proper steps, you can teach your adult dog house training in no time.
For older male dogs, this task can sometimes be a little bit harder as males has a tendency to “spray” in the house after living outside for so many years. However, this habit is not impossible to break and will simply take time and patience to overcome. Make sure your dog is neutered before beginning this process as it will make your training 95% easier in the long run.
House training any dog requires a steady eye and a diligent owner to watch them for signs that they are about to relieve themselves. As soon as they show those signs, escort them outdoors and repeat your potty phrase (ie: “go potty,” “do your business,” etc.) until the dog goes. As soon as you see him going, make sure you praise him like crazy until he understands that he did something very right! And do this every time he goes outdoors. Soon, he will grasp just what he is doing right that you love so much.
If a dog relieves himself indoors, never punish him or her. Always redirect (bring outside) and reward (praise, treats, etc) when they go outside. Dogs work better when you use the ignore/praise approach. Ignore the bad, praise the good. There are a variety of things he or she can learn that are exactly opposite of what you are trying to teach by smacking or hitting your dog. Not to mention, I’m sure you want your dog to respect you out of love, not fear; this is the way to ensure his trust and respect through positive reinforcement training.