Ingenico iWL255 Quick Reference Manual page 37

To change the paper roll, follow the steps below:
1. Pull up the flap at the top of iWL255 3G Long-Range Wireless.
2. Pull the flap backwards to open the paper compartment.
3. Place the paper roll into the paper compartment. Make sure the end
of the paper is inserted as shown below. Pull a little bit of paper out
towards the top of the terminal. Close the paper compartment by
pulling the flap up towards the terminal.
4. Close the paper compartment so that a little bit of the paper is
coming out.