If you’re like me and have trouble keeping up with your pup at all times try using a tether. You can buy a tether from the pet store or simply do what I did and use a long lead or leash. If tethering your pup to you at all times is what it takes to make sure they’re not sneaking off then go for it. If you’re not keen on keeping your dog tethered you can use baby gates or closed doors to restrict your dogs access to the whole house.
Just because your new dog is old enough that he should know where to potty doesn’t mean that he actually does. An adult dog has the necessary muscle control to hold it for longer periods of time, but if no one ever taught him the potty training rules then he’s the equivalent of a brand new puppy. Age should not be equated with housetraining prowess, so it’s a good idea to treat any dog new to your home as if he’s still learning the potty training ropes.
The process is the exactly same for older dogs as it is for puppies; prevent accidents from happening by using baby gates and a crate if possible, create a predictable schedule, learn to recognize your dog’s potty signals, accompany your dog outside and immediately reward for all outdoor elimination, properly clean any accidents and supervise your dog until you’re sure that he understands the rules.