A puppy is never too young to start obeying commands -- well, almost never. Most pups need to hit a certain age range before they'll start obeying your commands, and even then, you need to choose them carefully -- you won't have much luck with "Rub mama's feet, Rex."
Starting Out Young
Puppies don't have much growing up to do before they're receptive to learning -- usually, if your new puppy is old enough to go home with you, he's old enough to start getting an education. Puppies can start training and following commands when they're as young as 5 weeks old, though if it's your first time raising up a puppy, it may be easier to wait until yours is closer to 8 weeks old.
Don't Waste Time
When you're puppy is old enough to listen to your commands, it's time to get down to work. The first few months of life are when he picks up the socialization and obedience cues he'll adhere to all his life, and if you skip out on training, you'll pay for it in barks, bites and bad leash behavior later on. If you don't train him now, he can theoretically go the "non-traditional" student route as an adult, but it's much harder to break bad habits later than to learn good ones now.
Go to School
If you're worried that you can't effectively home school your pup, take some professional guidance in the form of puppy kindergarten and obedience/socialization classes. These classes usually start at around 7 to 8 weeks old, and for the next five weeks or so, your puppy is in prime mental development time. That means that in the right hands, he's primed and ready to learn everything he needs to know. The point of these classes is to prevent problems before they develop, so even if he's your sweet little angel now, ship his furry butt off to class.
Consistency and Leadership
If you want to start training a puppy while he's young, you need to be a consistent leader in the household. Dogs understand and respect hierarchy, so you have to make it clear that you make the rules, not him. This includes everything from maintaining a consistent feeding schedule to using commands like "Down" consistently. It keeps your puppy from getting mixed messages and it makes it clear that you're the boss.
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Writer Bio
Tom Ryan is a freelance writer, editor and English tutor. He graduated from the University of Pittsburgh with a degree in English writing, and has also worked as an arts and entertainment reporter with "The Pitt News" and a public relations and advertising copywriter with the Carnegie Library of Pittsburgh.