1. Season’s Greetings or Seasons Greetings or Seasons’ Greetings?
The correct version is “Season’s Greetings” because they are the greetings of/for the season—the apostrophe shows possession. Without the apostrophe, or with it after the ‘s’, it indicates multiple seasons. Another common error is to write “seasonings greetings.” Don’t be that guy.
2. Misspelling Christmas.
It seems so silly, but often people misspell the word Christmas. Pay attention to every letter on your cards so you don’t make an avoidable, cringe-worthy mistake. And please spell everyone’s names right.
3. Afraid of the Oxford comma?
When you have a list of things, don’t overthink the grammar and attempt an awkward or confusing way of saying the same thing to avoid the chance of being wrong. In the following example, both are correct: “We wish you happiness, health, and prosperity this Christmas.” or “We wish you happiness, health and prosperity this Christmas.” Whichever you choose is your preference, however, I will say that in some instances the comma makes your intent clearer. I would suggest making use of the Oxford comma on your Christmas cards this year.
4. Happy New Year or Happy New Years?
If your Christmas card goes on to send warm wishes for the coming year, make sure you are using the correct form of the sentiment. It should not be plural. If you were referring to a New Year’s card, then there is an ‘s’ but it is still not to indicate multiple years that are new.
5. Winter or winter?
When you are mentioning the season, it can be a little tricky to know how. Whether you capitalize depends on where it is in the sentence and how it is used. If the word is at the beginning of the sentence, it will always be capitalized. Other than that, it is a generic noun (not a proper noun) and does not need to be capitalized. An exception is if it is a title, like the Winter Olympics.