Sometimes, you might see that your labels are a bit off and need adjusting. You can adjust these margins and define new paper sizes by right-clicking on "Rollo Printer" and choosing "Printing Preferences"
Click on "Settings" and adjust the margins as desired. You may need to do some trial and error to find the perfect combination. You may enter both negative and positive values here.
Click on "Apply" or "OK" to send these settings to the printer for your next printing.