* Observation: Brian starts as a dishwasher and observes Doug Coughlin, a seasoned bartender, working his magic.
* Trial and Error: He learns by doing, making mistakes and figuring things out on his own.
* Self-Motivation: Brian is driven to be the best and pushes himself to learn new tricks and techniques.
* Mentorship from Doug: Doug, while initially reluctant, eventually becomes a mentor and teaches Brian some of his signature moves and philosophies.
So, while there isn't one specific person who teaches Brian how to tend bar, he learns through a blend of observation, practice, self-teaching, and mentorship.