Notes on this puzzle
Sudoku #5202 is a medium grid with 30 givens, which leaves 51 cells waiting for a digit. Played purely by logic, it takes 51 forced steps from the first placement to the last.
Most cells fall to the hidden single move: 50 of the 51 steps. Single candidate accounts for 1 more.
Among the givens, 1 is the most common digit (5 times) and 2 the rarest (2). The emptiest box is the central one, with 0 givens; the top-middle box is the most crowded, with 7.
Where to beginLook at row 1, column 2 first: a hidden single is available there from the very start. When scanning stalls, look for a cell whose row, column and box together rule out eight digits.