To automatically adjust margins and an interval between cards on the basis of the size of an optionally selected pop card without especially recognizing the size of a sheet allowed to be set in a printer.

When a previously printing/pop sheet design picture 31 corresponding to specified pop size is opened and sheet name tag 48 is specified, inputs from a number-of-vertical sheets input part 44 and a number-of-horizontal sheets input part 45 are received, and when an automatic control button 49 is clicked, a sheet of JIS size larger than the whole size of arrayed pop cards and most closed to the whole size is selected and right and left margins are automatically calculated to arrange the preparation of output data.