If it would not upset a lot of people, I would stay at home alone, watch only pre-recorded non-Christmas TV shows, eat my normal diet, turn off my phones, and ignore the whole thing. This party blackout would last through to the New Year, then I would get on with my life again, such as it is!
My sister rings me at 00:00:01 every Jan 1st to do the HNY thing. I never answer, but she keeps on doing it.
If I had the money, I would take a bike to somewhere warm and sunny and get a few hundred miles of cycling in while half of the population of the world went mad.
So ... as usual, it will be family, friends, and a few big meals for me, and no cycling!