Ah, it's always tricky finding the right way to address a Christmas card. It's important to show respect and appreciation for the recipient. You could try something like "Dear [name of recipient], Wishing you a joyous and blessed Christmas. Sincerely, [your name]." Or, if you're close with the recipient, you could use a more personal greeting like "Merry Christmas, dear [name of recipient]! With love, [your name]." Remember, the key is to convey warmth and good wishes.