[Galaxy S8/S8+] How do I install the SIM or USIM card on Galaxy S8/S8+?

Note: Only Nano-SIM cards work with the device. Use caution not to insert
the SIM card on position for memory card

Insert the SIM or USIM card provided by the mobile telephone service provider. 

Use caution not to lose or let others use the SIM or USIM card. Samsung is not responsible
for any damages or inconveniences caused by lost or stolen cards.
Some LTE services may not be available depending on the service provider.

• Dual SIM models: In some areas, data transfer speeds may be slower
if two SIM cards are inserted in the device than when one SIM card is inserted.

• Some LTE services may not be available depending on the service provider.

For more information about service availability, contact your service provider.