The Kuvasz has a very stubborn temperament and is used to making its own decisions. This comes from its long history of being used as a guard dog for livestock and nobility. It will tend to make up its own mind and it will want to control almost any interaction. This is a dog that is dominant and isn't afraid to push your buttons. You can expect that even when you think the dog is trained and taking your lead, that it may suddenly test your boundaries one more time to see if you really mean business. It is up to you to be consistently firm and not waffle or let the dog take the lead at any time, or it will think you are a pushover.
Even experienced trainers find the Kuvasz a bit exasperating to train. They are intelligent and quick learners, but that doesn't mean they will obey every command. They have the tendency to want to assert their dominance regardless of their training and will often choose to ignore a command in favor of their own judgment. The key to training them is to understand that they require constant reinforcement and a great deal of patience.
You will want to start when the dog is very young and easy to handle. Get the dog obedience training to help you be a good handler and to train the dog properly. This is not only beneficial for your skills as a handler, but also for socializing and laying down good rules for the dog to follow. It is also easier to handle a small dog and it will be conditioned to believe that the same control you had on it as a puppy is still present as it gets much bigger.
The dog's intelligence will also demand that its training challenge it mentally. This is not a dog that likes constant repetition and it will soon start to manipulate the training if it gets bored. You will want to not only provide interesting training activities, but also you will want to be even more stubborn than the dog. Show it you mean business even though the dog's willingness to test your limits seems endless.
One thing that does not work with a Kuvasz is harsh training methods. If the dog thinks it is being treated unfairly, it will dig in its heels and become remarkably uncooperative. You want to get its cooperation while controlling the situation, which means you will have to be firm, kind, and disciplined with a Kuvasz. If you can find the thing that motivates it the most, you will have an easier time getting the dog to cooperate. This means that you will eventually have to get into the mind of the dog to see if food, praise, or challenging activities make it an eager to please dog.