Learning how to choose a breed of dog is not a very difficult task. You simply need to determine what your lifestyle and requirements are, and find a dog breed that matches.
Some of the things that you need to match when you choose a dog breed are these:
1. Energy Level - If you are a person that is very active, choose a dog breed with high energy levels. A sporty person should choose a sporty dog who can keep up with extended levels of activity.
Likewise from a dogs point of view, an active, playful dog will get bored with a master who simply stays in the room without much activity.
2. Neighborhood - do you live in an unsecured neighborhood that makes you feel uneasy? If you are away from home for long periods, say you normally come home midnight, you may need a dog that can stand watch the whole time with minimal supervision. There are some breeds that you can simply leave some food, good for the day and they're okay.
On the other hand, in the same neighborhood, you may need a dog that can act as a companion, a bodyguard of sorts, when you walk the less secure streets.
3. Family - if you have kids, you may want to consider a dog that can be a companion or playmate to your children. Also, in the same manner, you will not want to have a dog known to serve only one master or with very undetermined temperament. You would not want to have a fierce dog suddenly lose temper and lash at your kids would you?
4. Health - If anyone in your family has allergies, you may want to get a dog breed that sheds less. If anyone in your family has allergies to animals, you may even want to forego getting a pet all together.
These are just of a few things you need to think about when considering how to choose a breed of dog. In the end, any dog you choose should be loved and cared for like any new member of the family.