Compose the message, tap Important button.
Tap Print, and then choose the Cubinote device.
Once the recipient receives your note, the Cubinote will print out the note and the button will be flashing orange light with beeping a sound until the recipient press the Cubinote button to confirm that the note has been received.
Once the recipient presses the Cubinote button, the sender will get a notification. That way you can be assured that they have received your note.