The Samsung Galaxy S3 allows you to expand the storage of the device by utilizing a Micro SD Card. You can insert and remove the SD Card by using these steps.
1. Turn the device off.
2. Remove the rear cover of the device.
3. While viewing the rear of the device, locate the SD Card slot on the right side above the battery compartment.
4. To insert a card, simply slide it gently into the side slot with the connectors pointing downward toward the screen. You should hear the card “click” into place. If you wish to remove the SD Card, gently push the card into the slot. It should “click” and eject from the slot, allowing you to easily remove it.
5. Replace the rear cover.
Power the Galaxy S3 back on, and you’re ready to go.