How do I insert the SIM Card on my Galaxy S3?
Insert SIM Card
Your mobile device uses a SIM card to provide you with access to your carrier's 4G LTE cellular network.
IMPORTANT: The SIM card information and its contacts can be easily damaged by scratching or bending, so be careful when handling, inserting, or removing the card. Keep all SIM cards out of reach of small children.
Insert a SIM Card
1. Remove the back cover by inserting a fingernail or pointed object into the slot on the top side of your phone (1).
2. Lift the cover up (2) and away from the phone.
3. Remove your device's battery.
4. Carefully slide the SIM card into the SIM card socket until the card locks into place.
NOTE: Make sure the card's gold contacts face into the phone and the upper-left angled corner of the card is positioned correctly. If the card is not inserted correctly, the phone will not detect the SIM card. Reorient the card back into the slot if the SIM card is not detected.
5. Insert the battery into the opening on the back of the device, making sure the connectors align (1). Gently press down to secure the battery (2).
6. Place the battery cover onto the back of the phone (1) and press down (2).
7. Press along the edge of the battery cover to ensure all of the clips have locked in place (3).