Have Your Money Ready When You Order – when you get to the bar, know what you want to order and have your money ready for the bartender when they come back with your drinks.
Don’t Use Your Credit Card Multiple Times – many people may not realize this bar etiquette
Running credit cards through is a time-consuming process that takes away from serving other guests.
BRING CASH
As John Carney pointed out on Business Insider, stop pulling out your credit card for one drink. You’re not only wasting the bartender’s time and delaying his tip by at least a week, you’re slowing shit down for the rest of us. Go to an ATM and pay the fee they charge you to not waste everyone else’s money.