If you choose to rescue a lost or stray dog, you are a hero. This surprisingly is not something everyone can do or is willing to do. It takes a special person to rescue a stray dog that they know nothing about or have any attachment to. Just because a dog is a stray does not make it a bad dog. An animal has no control over how it is raised or what happens to him. This is an innocent animal that has feelings and needs someone's help.
The first thing you need to do when approaching the dog, is to be very careful. You never know what kind of behavior a dog will have. Use food preferably to coax the dog onto a leash or at least over to you where it can feel a bit more comfortable.
Next you need to take the dog to the vet immediately. You need to make sure the dog did not contract any diseases living outside.
Then you need to make sure that the animal does not already have an owner. You should post flyers around the neighborhood and possibly even place an ad on the radio and or TV.
Next you should introduce the dog to its new environment. Try and make the dog comfortable with its new surroundings. Even though a home may seem like a safe place, the dog is only familiar with what environment it's already been in so it has to adapt and become familiar with its new environment.
Next you want to start training the dog as soon as it comes home. This includes housetraining, chewing up furniture, and biting. This will make the process much easier for the dog and the owner. The dog may actually be excited to learn, so start as soon as possible.
You want to take the dog on as many walks as possible with a leash so it can get used to being connected with its owner. If the dog is vicious or appears to be vicious, you may want to consider a muzzle or some other contraption.
Last but not least, you want to have your dog on a routine eating schedule so it can have consistency and know when eating time is.
Now that you've rescued a stray dog and gave it a nice, warm, loving home; have fun with your new pet. Show it all the love it's been missing and just play and have fun together. You are a hero in this dog's eyes.