The traditional way of spending Christmas is by sharing and gift giving but to romantically inclined people, this is the best time to give a unique present by giving a proposal. Have you seen a movie where a man popped the question like "will you marry me" while he unwraps the small ring box on Christmas eve? Isn't that sweet and romantic?
Some people may think that a proposal should be done in a separate event and not during holidays, valentines or birthdays. But in my own point of view, it is a grand celebration and will be remembered because of that special occasion on the time you propose.
There are a lot ways how to give your loved ones with this kind of gift. It will be a complete surprise if you plan it well like announcing when you're both surrounded by friends and family. Always be unique when creating an engagement proposal. Don't make it like the same scene in the movie that you watch a thousand times. If you think you are creative by making prank ways to surprise her, don't. At many times it succeed, but at times it failed too. It might end up with the girl to walk out or worst won't show up for the rest of her life.
Engagement, even if done on holidays can be also special. You can make it during another occasion just don't make it as holiday gift because it will only make the girl thinks that the man wants to make it a two-in-one event that sounded like another economical way to celebrate.