We shall act now
I think happiness is the most pleasant feeling ever. Not every person is happy, but everyone can be, you need only to have a wish.
The International day of happiness is a chance to share happiness with everyone.
As for me, our nearest and dearest are the first people we have to make happy every day. At school we played a game "Bingo of happiness" - there were some deeds which we could choose to do. I did a few tasks from the bingo and saw pleasant emotions and feedbacks from my family and friends. I understood that I have to make people happy every day, not only when I have time to do it, because our life and time are limited, so we need to make great things now.