A printing apparatus, method and storage medium therefor for executing trial printings. The apparatus includes a printing unit, a setting unit, an inputting unit, and first and second controlling and accepting units. The first controlling unit controls to execute first trial printing according to inputted image data and a set printing condition. The first accepting unit can accept a changing instruction for changing the printing condition. The second accepting unit can accept an execution instruction for executing a second trial printing. The second controlling unit controls to execute the second trial printing according to the inputted image data and the changed printing condition. When the first accepting unit accepts a changing instruction, the second accepting unit can accept an executing instruction. When the first accepting unit does not accept a changing instruction, the second accepting unit cannot accept an executing instruction.