We are going to assume you have done your breed research and selected a puppy suited to your lifestyle, and are now in the early stages of bringing it home.  Before you put down your money there are some things you need to take care of.

If you rent, make sure you have your landlords permission to get a dog, get this in writing.

Dogs do much better in a fenced yard than tied up. A dog run is fine if your yard is not fenced, but chaining dogs is illegal in some areas and is known to contribute to behavioral problems in many dogs, as well a dog on a chain without a fence is an easy target for stray dogs. So, make sure your your yard has a good fence, high enough that the dog cannot jump over, or invest in a dog run.

Will your dog be mostly inside or mostly outside? Outside dogs will need dog houses, or some other shelter, like access to the garage. Inside dogs will need a designated place to sleep, so make sure you decided in advance where this will be. Your new puppy, will very likely need to be house trained, the best method of doing this is crate training, as such you will need an appropriate crate, but do not start buying these items just yet.  See the Link at the bottom for how to do house train a puppy.

One of the only things you should buy before getting your pet, are the bowls. These should be stainless steel or ceramic, not plastic. Plastic bowls cannot be washed properly, they will allow bacteria to grow, and are major cause of canine acne. If you do get plastic bowls, they need to be replaced every six months. 

Next Step – Shopping for Supplies

Once you have selected your puppy, or dog, ask them to hold it for 24 hours while you get supplies. Find out what kind of food the dog is on. You should get a bag of that food, and if you are going to be switching the diet, you should get a bag of the other food, because you want to make the switch gradually. Find out what kind of toys the dog likes, some prefer balls, others like rope toys. If your new pet is going to be a puppy, you will need a multitude of selection in toys, some for teething, some for playing, and some for tearing apart. If the dog is older, it probably only wants a few toys, like a ball or stuffed animal. Find out what kind of treats it likes, and if it has any food allergies. What size neck does it have? Ask if there is anything special the dog needs, and what it comes with.

Then go shopping, your list should look something like this

1. Puppy food. This should be mostly dry food. Larger dogs are often not feed canned food. Avoid getting the semi-moist foods, as they are low on nutrition.   If the pup is a large breed be sure to get a large breed formula.
2. Collar and leash. At first you only want a short leash, do not get a choke collar.  Smaller dogs often walk better on a harness.
3. Bowls, if you did not get them already.
4. A crate.  For pups it is used for house training, for small dogs it is great for transportation. The crate should be large enough for the pup to stand up in, and turn around, but no bigger.
5. Toys, as mentioned, you want soft toys, like stuffed animals, medium toys, like rope toys and rubber, Kong type toys, and hard toys, like Nylabones. Get one of each now, and more when you find out what your new puppy likes best.  Teething is natural you must provide appropriate toys.
6. Treats. For house training, soft treats are a must. Some hard treats are good too, select healthy treats.
7. Doggy Bed or dog house. The dog bed does not have to be anything special, it can even be a blanket from a second hand store.  Both are optional depending on your situation.
8. Grooming supplies, brushes, nail clippers. Dogs who shed are generally less maintenance than those who do not, because the dogs whose hair is always growing, must be brushed daily to prevent painful tangles. Make sure you have the right kind of grooming supplies for your dogs coat.
9. Identification, or dog license.

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Get Ready

Go home and dog proof your house. Make sure there is nothing the little one will chew or could choke on. Talk to all family members so they know what to expect and that they should give the new addition space and time to adjust to its new home. If you have young children, they must know to respect the dogs space, and need for quite time.  Puppies should never be bothered while in their crate, this is their den, their safe space.

Be aware your puppy will not be fully house trained and that house training can take some time.  Try to avoid using newspapers as this may confuse your pup.

Health

Make sure you get a written contract, which should include the health guarantee. Never pay for a dog without getting any health guarantees. Make sure you get a copy of the vaccination record, and again, never pay for a dog who is not vaccinated. The dog should have also been dewormed prior.

If your new dog or puppy is not fully vaccinated, it should not leave your back yard until you have boostered the vaccination.

The First Week

Do not make any changes in the pups diet for the first week.  It may show signs of tummy upset from the stress and may be drinking different water.  Remember this is like taking a human toddler from its mother. 

Do not let it roam your entire house.  This may be overwhelming and additionally accidents are bound to happen.  Try keeping it in a smaller part of your house, preferably on a lino floor (not carpet). 

When you crate the pup at night it will cry.  This is because dogs are pack animals and it wants its family.  You can leave a radio on, or a ticking clock.  If you attend a crying puppy at night you will effectively train it to make noise when it wants attention, so it is best to put it in the crate for the night and leave it, again read up on house training.

Keep the treats to a minimum in the first week.  This is to avoid tummy upset.

As mentioned in health, do not let a pup who is not fully vaccinated out of the safety of your back yard. 

Related Links

House Training a Puppy

Understanding Ingredients in Dog Food

Where to Buy Puppies

Six Mistakes to Avoid making with your Dog