Sudoku Tips: Use a pencil, not a pen

Sudoku puzzles come in different formats:

• digital Sudoku, whether on handheld devices, or online
• Sudoku printed or written on paper
• Sudoku games made out of plastic, wood, or similar

If you’re working on paper, be sure to use a pencil, not a pen, and have an eraser handy. You’re bound to make the occasional mistake, which you’ll want to erase.

Plus the pencil will come in handy for marking up the possibilities for the empty cells that can’t be solved with simple scanning techniques.