TIP #1: ATTENTION!
If your dog ignores you when you ask him to do things is he just being stubborn? No, it just means you don't have his attention. Teaching a Look or Watch cue - getting your dog's focus with a single word - is very useful. You can distract him from enticing trash in the street, for example, or keep his eyes on you when walking past another dog. Plus, dogs that are rewarded for paying attention do it more. And attentive dogs are easier to train.
TIP #2: PREVENT RESOURCE GUARDING
Whenever you pick up your puppy's food bowl, whether to fill it or to clean it after her meals, offer her a treat.
Jeff Dentler, CPDT-KA, CTDI