What you need
- Card terminal either C100+ or C10.
- Plastic protection for keypad.
- Some way of cleaning the keypad.

Step by step
- Clean the surface of the keypad.
- Remove the plastic cover from the paper.
- Apply the sticky surface to the keypad. Make sure that the holes are aligned with the two white dots on the keypad. Those are there so you can attach the pin cover as well.
- Firmly press the plastic from the inside out.