(Wait, it's late December already? Oops. I guess you'll know for next year.)
Osechi ryouri - おせち料理 - is traditionally eaten on (or around) New Year's Day. It usually includes foods with 'lucky' names and colours. Like 'daidai' bitter orange, which in different kanji can mean 'from generation to generation'. Ah, wordplay and food. A lovely combination.
Red, white, and red and white foods are both meant to bring you good fortune. Sounds suspiciously like Christmas to me!
Thinking about sitting down to some osechi on January 1st? You'd better have ordered it before Christmas. Reservations open at around the same time as those for cakes.
The other New Year's Day activity to prep for hatsmoude (初詣). Making your first shrine visit of the year - ideally on the first day of the year - is VERY important.
Shrines and temples get incredibly crowded. Many people get time off for 'nenmatsunenshi' (年末年始) between Christmas and New Year. This often lasts to around January 3rd or 4th. So the first 3 days of the year are all popular for making shrine visits. Japan's biggest and most well-known shrines host millions of visitors over those 72 hours.
It's cold, and probably dark outside, and maybe raining, and a bit miserable. So this is clearly when you need religion the most...
When you get home, you might find a nengajo (年賀状), a New Year's card, waiting in the postbox. You guessed it by now - the sender wrote it in December and had to perfectly time their postage.
January 1st is considered the best time to receive a card. In fact, Japan's Post Office won't accept them for sending before mid-December, because they'll arrive too early.
Last year, the first posting day for nengajo was December 16th. The latest you can send them for a New Year arrival is Christmas Day. Allow a bit more time if you're posting internationally.
Once you've read your nengajo, hold onto it. There'll be a code on your card if it was bought from the Japan Post Office - it's a lottery number. There are prizes for matching 2, 4, or all 6 of the numbers.
This year, the top prize is a holiday or other experience, OR 100,000 yen. One in every million cards will have all 6 matching numbers. Sounds impressive, but the Post Office is issuing a lot of cards. So 2,867 of them have the winning combination.
With so much to think about, if you're celebrating a New Year in Japan then you've got to be ready. It might even be worth considering your plans for 2018 starting from now...