Say 明けましておめでとうございます (also short for あけおめ) to everyone you met for the first time in the new year.
今年もよろしく (short for ことよろ).
This year please take care of me.
元旦
New Year’s Day
お年玉
New Year’s gift money
お年賀
New Year’s Gift
お節料理
Food for New Year Holidays