Next certificate will be —. Numbers are never repeated. Change
Print alignment (gold foil paper)
Do a test print on plain paper and hold it behind a foil sheet against a window. If the art touches the foil, raise the margin. If it is off-center, shift it (negative = left / up).
“Test print PDF” makes an unnumbered sample of the student shown in the preview so you can check alignment on plain paper. It does not use a certificate number. Print at Actual size / 100%, US Letter landscape.