1. Place your device on a flat, clean surface with the display facing down.
2. Use your fingertip to pull out the SIM/SD door.
3. Use a small pin or paperclip and insert it into the hole beside the SIM/SD tray and push gently. The SIM/SD tray will pop out. Use your fingertip to pull out the SIM/SD tray.
4. Place the first SIM card on the SIM 1 slot of the tray with the gold pins of the SIM card facing up.
5. If you would like to either use a microSD card or a second SIM card, place that on the SIM 2/SD slot of the tray with the gold pins of either card also facing up.
6. Carefully insert the tray back into the slot.
7. Push the SIM/SD door back in until it is fixed securely.
Note: Some devices take two SIM cards. When two SIM cards are inserted, both SIM card slots can support 4G/3G service.