Young puppies can’t hold their bowels & bladders for long. If you come home to find that they’ve had an accident in there it’s quite possible that they can’t hold it that long. Generally puppies can hold their bladder for about one hour per month of age. So your 3 month old pup can probably only hold their bladder for about 3 hours. If you’re going to be away at work for long periods of time see if you can get a neighbor, relative or dog sitter to come over to let your pup out during the day.
When you have to leave the puppy alone, you’ll need to confine it to a crate. This will prevent the puppy from peeing and pooping all over your home, and will also help teach it control, since it won’t want to soil the crate. However, young puppies need frequent bathroom breaks, so you’ll also need to ask a friend or pet-sitter to stop by and let the puppy out throughout the day until it’s old enough to go for longer stretches without needing to use the bathroom.
Every time your dog pees or poops outside it needs to be celebrated. Give them baby talk or a treat, jump up & down, pat their little heads & remind them of how brilliant that decision was. Yes it might look silly, but your pup needs to know he’s done the best thing ever. When you consistently praise your puppy for going potty outside they’ll start to understand that it’s the correct decision, and one that leads to super fun happy time.
I don't teach or recommend so-called "purely positive" methods that allow misbehaving pups to continue misbehaving, instead of teaching them which behaviors are and are not allowed. "Purely positive" is fine for teaching tricks and high-level competition exercises, but NOT for teaching the solid good behaviors that all family dogs need to know, and NOT for stopping behavior problems such as barking, jumping, chewing, nipping, chasing, etc.
Remember that training is an ongoing process. You will never be completely finished. It is important to keep working on obedience training throughout the life of your dog. People who learn a language at a young age but stop speaking that language may forget much of it as they grow older. The same goes for your dog: use it or lose it. Running through even the most basic tricks and commands will help them stay fresh in your dog's mind. Plus, it's a great way to spend time with your dog.
Dogs thrive on a predictable schedule, and setting one up for your new puppy will make life easier for both of you. Feed your puppy at the same times each day to help you predict and schedule bathroom breaks. Schedule post-meal walks, as well as hourly trips outside during the initial stages of potty training. Always take your puppy out after crating, even if was only for a short time, and remember that vigorous play should always be interrupted for potty breaks.
You can use potty training pads to give a puppy a place to go inside. They are usually scented in order attract dogs to urinate on them. This can be an aid in potty training and may seem necessary depending on your situation. But, it can also cause some problems that may prolong the training period and make it more difficult. Using pads can confuse a puppy into thinking that it is OK to go inside.
Introduce your new pup to its new home, family and their role. Just like when you are new to a place or group, your new pet may be bursting with curiosity, excitement, fear or joy. Now is the best time to lay out the foundation for a good and pleasant relationship with your pet. For a puppy to settle in and learn to trust and respect you and everyone at home, it is very important to establish your expectations of your puppy and be consistent with them.