One of the most powerful tools we have when working with dogs comes from within.
The more knowledge we gain, the more confident we become. Self-confidence layered with our energy (emotions x intentions) becomes one of the most important tools we can use while interacting with Mother Nature.
Dogs can not follow anything that is unstable. Meaning, they won't feel safe following a human that is uncertain, frustrated, anxious, etc.
That is why confidence becomes such a great tool to practice and grow within ourselves. Watch Sadie change very quickly as her owners become more familiar with dog psychology and more aware of how they feel.