Reddit reviews Decoding Your Dog: Explaining Common Dog Behaviors and How to Prevent or Change Unwanted Ones

One that should be on your reading list if you haven't read it already: Patricia McConnell's The Other End of the Leash.

I think Decoding Your Dog may be pretty useful, too.

Please, for your dog's sake do NOT rely on Milan techniques. He uses extremely out-dated and sometimes even dangerous and damaging methods.

Here is a fairly well written website explaining a lot about why his methods are not scientifically accurate, and I believe also going into actual dog behavior.

Here's another very well written critique of Millan, with corrections and real dog behavior. More biased, but good information.

Finally, I highly HIGHLY suggest reading "Decoding Your Dog" which is a very in depth explanation of a lot of aspects of dog behaviors, all backed by science and written by veterinary behaviorists.

I hope this is the least bit helpful! I think you'll find you enjoy your dog once more when you let go of the untrue, macho idea that you must "dominate him" at all times. Be his best friend instead!

Whew, ok, lots to unpack here.

First question: does your dad know you're about to give him a GSD puppy? You're signing him up for a pretty big 2 year commitment here (and that's just the puppy phase), so please make sure he's 100% on board with the idea of raising a landshark demon spawn before bringing it home.

Secondly, breed standard puts an adult GSD somewhere in the neighborhood of 24" tall and 60-80lb. This can vary widlly based on sex, line, and breeding quality. My poorly-bred GSD male is 29" tall and a scrawny 85lb. I've also seen some pretty petite females come through my rescue.
On the subject of lines, do you know what kind of GSD you're getting? There are various working and show lines, and the personality and structure of your GSD can come out all over the map. If you don't know the answer from talking to your breeder, run away, because you're not getting a well-bred dog. Poorly-bred GSDs are health and temperament nightmares.

Thirdly, the breed standard calls for a confident but aloof personality, but again, temperaments may vary depending on lines and breeding quality. GSDs need to be socialized thoroughly but carefully to lock in that confident-but-also-aloof sweet spot. Flooding your puppy with tons of new people and places will create a fearful adult, but so will keeping your dog locked up. I have seen lots of success using a puppy-led gentle exposure technique. Take your dog to lots of places, but don't make the novelty into a big deal. Don't force your puppy to interact with every person and dog you see, and call it a day if your puppy seems overwhelmed or scared. A puppy builds confidence by exploring on its own, you're just there to moderate the experience and make sure it's a positive one. I can't recommend a group obedience class enough for young GSDs...learning to focus in a controlled environment around other dogs is a valuable asset for future life skills. Consider finding a local trainer that does group positive reinforcement based training, or at least very positive-leaning balanced training. Avoid anyone who mentioned "alpha" or "pack leader" because that school of thought is outdated and disproven (but is holding on forever in GSD breed circles for some reason). Also avoid anyone who wants to put a prong or choke collar on your dog without evaluating their behavior first.

Honestly, if I were you I'd stop and do a little more research before bringing home a GSD. They're a little more of a "lifestyle breed" than your average family pet, and will find and exploit any weakness in your dog-owning abilities. Read some books (recommendations here: 1 2 3 4), talk to your dad, take a good look at your breeder, maybe find a local trainer with a good positive puppy class, and try again with a little more information under your belt.

Source ahead of time: work at a vet clinic and have taken my dog to our state's veterinary school's behaviorist department.

Probably late to the party but okay. Like everyone said: positive reinforcement positive reinforcement positive reinforcement, and a lot of redirection and avoidance of problem. Every time your dog has the opportunity to misbehave, he is reinforced with the idea that this is an acceptable and functional way to go through life.

So for example, my dog has fear-based aggression issues. This means we do not under any circumstances give him the opportunity to be approached by strangers, or to approach a stranger in a circumstance in which he might feel threatened or cornered (and might, thus, make the decision to bite or otherwise behave aggressively). Ninja edit: and we do not discipline or rebuke him, because this only heightens the anxiety and thus the aggression, and can sometimes result in misdirected aggression towards you, the owner, instead.

As others have said, again, you want to give the dog a good behavior to replace the bad. Teach them to sit instead of jump, if they bark remove them to a separate room with a peanut-butter filled kong toy (but be careful about peanut butters, as some have an artificial sweetener that can be harmful to your pup! so ninja-edit two: squeeze/canned cheese is also a great low-cost option!), explore local resources for clicker training or puppy schools (but avoid shock collar trainers IMO), and always be aware of what behaviors you are rewarding either intentionally or accidentally!

(So for example, if the dog is barking, don't throw him a treat; wait until he has stopped barking for ~1-2 seconds and then treat him. This may seem counter-intuitive, but as far as canine cognition goes, he will understand this as a reward for silence, I promise!)

I highly recommend Decoding Your Dog for a lot of great resources on training and otherwise understanding the why of canine behavior. It's not a be-all end-all source, but it's a really great first step towards how to address behavioral issues and combat them in a healthy manner!

There's actually no evidence to support the old wives tale that dogs try and form interspecific dominance hierarchies. At least not with humans.

Source: literature by veterinary behaviourists include this book which I recommend if you ever get a dog or puppy.