To prevent damage to the SIM card, always remove the battery before you insert or remove the card.
A SIM card may be already inserted in the device. If not, do the following:
Open the cover of the SIM card slot.
Insert a SIM card in the slot. Ensure that the contact area on the card is facing up and the bevelled corner is facing toward the device. Push the card in.
Close the cover of the SIM card slot. Ensure that the cover is properly closed.
If the SIM card is not properly in place, the device can only be used in the offline profile.