Fill in the grid so each row contains the digits 1 through 9 exactly once
Fill in the grid so each column contains the digits 1 through 9 exactly once
Fill in each 3×3 box so it contains the digits 1 through 9 exactly once
Use the given numbers as fixed clues
Look for rows, columns, or boxes with only one possible missing number
Eliminate candidates by checking intersecting rows, columns, and boxes
Use process of elimination to place numbers
Repeat the scan and elimination steps until the puzzle is complete
Do not guess unless necessary
Verify every placement against Sudoku rules