To lead, coach, teach, parent, influence, or sell, you can study lots of techniques. And I recommend you do.
To do these very well, cultivate your belief in others. Develop such a strong belief in each person’s abilities, potential, and future successes–even before you see any evidence–that they begin to believe it, too.
To your continued success,
P.S. If you have trouble imagining that this could work, consider this: What would happen if you believed the opposite? Also, you don’t have to believe something ridiculous. Just believe something that is even a little bit better than what they are now.