“Hey, you!” will just earn you a cold shoulder. Try these moves

Gain respect

He’s not your “buddy,” 
and she sure as hell 
isn’t your “darling”. If 
you want a drink, make eye contact. Your bartender keeps a mental waiting line. A look locks you in. Finger snaps move you to the end.

Nail the tip

It’s 10% of your total 
bill, right? Yes, 10% is generally the standard service charge, but if you think the service was great (and you want to keep it coming your way), add in some extra. And don’t forget a thank you.

Be sincere

Common barkeep myth: they like hearing about your problems. To build rapport, talk with the man, not at him. Ask where the best craft beers are being brewed these days. Then mention a sports team or why’re you in the city.

Respect the limits

It’s okay – nice, even – to offer to buy the bartender a drink, but understand if you’re turned down; after all, they’ve have bosses too. When you make your next order, just say, “…and one more for you if you’re interested.” It’s an open but no-pressure invitation.