If your Skyboxe did not come with a pre-installed SIM card, then eject the SIM card tray by inserting the provided tool into the pinhole. Insert a nano SIM card with a data plan into the tray. Keeping your Skyboxe flat on a table, carefully replace the tray, keeping the pinhole on the left side.
Do not insert the tray upside-down. You could permanently damage your Skyboxe.
Do not stand your Skyboxe up on end while inserting the SIM card. Your SIM card could fall out of the tray and become lodged inside the device.
Click here to watch a short video showing this step.