First You will need to tame a Vanilla wolf.
Then right click on the wolf with a training treat. And he will become a dog.
To make sure he is right click on him with s stick and it will come up with the Dogs Gui, where you can rename your dog and add talents to him.
As you see now there are less talents (At the moment more coming soon) that the original mod. You can now rename him and a label will appearer on the dog.
To level up your dog simple right click agian with a training treat. For every level you dog goes up you dog gets 1 point to spend on talents.
Once you dog reachs level 20 you will have to use Super treats then once it reachs level 40 you will have to use Master treats. This will take you dog to level 60. After that you can use Dire treats to up his dire level. Once his dire level reachs level 30 he will get more health and attack strenght and will have ender portal particles around him.