The past weekend I walked to my neighborhood wine shop to pick up a hostess gift. I was able to pay with a $20, but I walked out with a nice bottle of wine and $12 cash.

I was only supposed to receive $3 back.

Yes, I walked back in to explain that I’d been given too much change, and the clerk just looked at me like I was crazy. When he had just shoved the cash in my hand, he had no idea he was giving away the store.

This is a harried time for you and your employees, but it’s worth 300 seconds of everybody’s time to remind them of the best practices for handling money during the holidays.

1. “Out of $10?” It’s always a good idea to say aloud to the customer the amount tendered. When the total is $9.95 and you say “out of $10?”–that’s the time for the customer to correct you if they actually handed you a $20.
2. It’s also a good idea to rest the cash paid on top of the cash drawer–or someplace out of reach–until you count the change back. Then if a customer says, “but I paid with a $20” you can show them the actual $10 bill they handed you. After you complete the transaction, you can put the cash tendered in the drawer.
3. This brings me to another good practice: Count back the change. Customers actually like having their change counted back, and it’s not a difficult concept to to teach your staff. If you start with the amount owed and count up to the amount paid, there’s no subtraction involved. If the amount owed is $5.63, most customers won’t mind if the coins aren’t counted back. You can place the 37 cents in their hand when you say “37 makes 6.” But when you hand over the remaining $14, they’ll love to hear the “7, 8, 9, 10, and 10 makes 20.” I promise.
4. When the wine guy handed me a $10 and two $1s, it could be because the $10 was inadvertently placed in the $1 slot in the cash drawer. This is why it’s a good idea to have all of the bills facing up and in the same direction. It makes it easier to find any bills mixed in with other denominations.