A good barista is like a good barkeep. Keep the drinks and conversation coming. As it with good business: Avoid the nonsense, and be real. Communicate well. Enjoy what you do. Listen. No false claims about what coffee can do (it won’t help me lose weight, grow taller, or make me a better lover). Be congenial and know when to shift gears. Understand the business arrangement doesn’t limit courtesy and kindness.
And… hey, why aren’t you pouring? I said keep the drinks coming.