International Sudoku Day takes place, of course, on September 9 (9/9). Sudoku enthusiasts will no doubt notice the date’s symbolism. The goal of the Sudoku game is to fill a 9×9 grid so that each column, row, and 3×3 sub-grid contains all the digits from 1 to 9. So nine-nine is the natural choice for the day of celebration. It’s time to get your brain into gear because although today is most definitely a cause for celebration, some hardcore logical thinking will be required.

HOW TO CELEBRATE INTERNATIONAL SUDOKU DAY

1.     Solve some Sudoku puzzles

There’s no better way to observe International Sudoku Day than to solve some Sudoku puzzles! You can do as many or as few as you want, but challenge yourself.

2.     Buy some new puzzle books

Out of puzzles to solve? Make International Sudoku Day the day you replenish your supply. If you’re a Sudoku connoisseur, hunt around for the most challenging puzzle book you can find. If you’re a newbie, there are plenty of entry-level books for you. Either way, get a new book and solve those puzzles like there’s no tomorrow.

3.     Challenge a friend to play head-to-head

Sudoku doesn’t have to be a one-person activity. Take the challenge to the next level by competing against your friends. Whoever solves the puzzle fastest, wins. You can all participate at the same time, or create brackets to narrow it down to the best puzzle-solver. The winner gets bragging rights and now you’ve emulated the spirit of the World Puzzle Championship, right in your living room!