Open the program and set the color mode to CMYK. After that, navigate to the Edit menu and select Insert Barcode. From the Barcode Wizard, select a barcode type, enter 11 numeric digits and if you want 2 or 5 more for a barcode add-on. Click Next, choose a printing resolution and the barcode dimensions and press again Next. Select a font, click Finish and save the file. For further details, check the official user guide.