A supporting program causes a computer of an information processing device to display a setting screen for receiving an input operation of print settings, and acquire sheet information representing information of a sheet a printer uses for printing. Further, when there is a print instruction output from an application program and instructing a general-use printing program implemented, in advance, in an operating system, to perform printing of an image, the computer performs acquiring sheet information included in the print settings and determining suitability of a sheet by comparing the sheet information acquired from the printer with the sheet information of the print settings. The computer displays a warning message for a user when it is determined that the sheet is unsuitable.