If it's a note wishing someone a Merry Christmas:
* Carte de vœux de Noël: This is the most common and formal phrase for a Christmas card.
* Message de Noël: This is a more general term for any Christmas message, including a note.
* Petit mot de Noël: This translates to "little Christmas note" and is more informal.
If it's a note with a specific purpose related to Christmas, like a list or a reminder:
* Note de Noël: This is a simple translation for a Christmas note, but it's not as specific as the other options.
* Liste de Noël: This is used for a Christmas list.
* Rappel de Noël: This refers to a Christmas reminder.
You can also use phrases like "une note pour le Noël" ("a note for Christmas") or "un message écrit pour Noël" ("a written message for Christmas").
Ultimately, the best translation depends on the specific content and purpose of the note.