Between bellhops and hairdressers, cab drivers and valet parkers, proper tipping can be tricky territory.

To keep it simple, etiquette expert Bridget Weedn has a standard rule when it comes to tossing someone a little something extra.

“Twenty percent is pretty standard,” says the owner of Etiquette Consulting in Fox Chapel. “Twenty-five or thirty, if you’re particularly pleased. Even if the service is poor, stay at 20. You have to consider the fact that a lot of servers only get income from tips. If the service is that poor, report it to a manager.”

Weedn thinks tips should go to anyone who helps you out, from the doorman at the hotel to parking attendants at the airport – even if the situation isn’t always one that should elicit a tip. “A particularly helpful funeral director or an accommodating church volunteer are often worthy of a monetary donation,” she says.

When you find yourself in a situation where the person is not allowed to accept a tip, Weedn suggests finding a way around the rule. “I was at Sam’s Club and the cashier went above and beyond to help get me a cart and extra boxes. She was not allowed to take a tip, but the store was accepting donations for the Kidney Foundation, so I donated in her name,” she says.

Another option is to alert management of the job well done. This way, the business could compensate the employee through a bonus or even a raise. In this day of debit cards, Weedn stresses the importance of always carrying some cash just in case you find yourself in a tip-worthy scenario. She suggests stashing at least $100 in your pockets at all times, and make sure some of it is in the form of ones and fives. She also recommends tipping waiters in cash, just to make sure the money gets to the right person.

And when it comes to handing over the tip, staying discrete is key. Weedn suggests folding the money and never asking the receiver for change back. They might not have time to get it for you, which could cause some embarrassment on both parts.

“That’s a poor reflection on you,” she says.