Image: Santa Claus © John Lund,Jupiterimages

Regular, everyday tipping etiquette apparently wasn't baffling and awkward enough. So holiday tips have been added to the fray.

OK, maybe year-end tipping rules weren't invented just to confuse you. But that can be the result when you're not sure whom to tip and how much.

Holiday tips are cash bonuses or other presents customarily handed out in December. They're a way of saying "thank you" to the people who provide you with services year-round. But the rules for holiday tipping aren't set in stone, and they’re changing as society changes, said Peter Post, the managing director of the Emily Post Institute and the author of "Essential Manners for Men 2nd Edition: What to Do, When to Do It, and Why."

Here's what is important to know this year:

Holiday tips should fit within your budget. "You shouldn't put yourself in debt," cautions Post, the great-grandson of the legendary etiquette expert. If you can't come up with the recommended amount of cash for each person on your list, you can tip less, give a gift instead or, if your budget's really tight, consider something homemade, such as a plate of cookies.

Set your priorities. As you're making a list of people who might deserve a holiday tip, "identify the people who have really done something special for you" above and beyond the usual level of service, Post recommends. Those are the folks who should be at the top of your holiday tip list. Further down the list, add the people you tip generously (20% or more) throughout the year. If you can't scratch up the recommended cash for these service providers, you can leave a larger-than-usual tip in December, or give a card, small present or both. People who needn't be on your holiday tip list at all include schoolteachers (gifts or gift cards are more appropriate) and U.S. Postal Service workers, who are forbidden by USPS ethics rules from accepting cash (although a gift worth less than $20 is OK).

Consider pooling tips. Post especially likes this approach when dealing with holiday tips for building superintendents, doormen and building staff where unequal tips could lead to unequal service. "Is the person who gives $75 going to get faster attention than the person who gives $25?" Post wondered. If that might be the case, then a gift pool would allow each person to give what he or she can afford without fear of reprisal. (Pooling resources also can work well when buying holiday gifts for teachers or tipping daycare workers.)

Ask around. Holiday tipping customs can vary by region and by type of establishment. Bigger tips may be the norm in larger cities or deluxe buildings, for example. Ask other people what they give, or call the establishment to find out what the range of holiday tips generally is.

Don't forget the card. The tip or gift should be accompanied by a card with a handwritten note expressing your gratitude. A couple of sentences is all you need to squeak out.

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