Connect the GSM module to your PC, via USB. Install USB driver, if needed [USB drivers are available in downloads section].
Start the modem having the SIM inserted into the SIM slot.
Open your favorite terminal utility [we use Terra Term]. Open the USB serial port, selecting 115200bps.
Proceeed with following AT exchange [we assume the PIN CODE is "0000", replace with your SIM card PIN code!!!]:
AT+CPIN?
+CPIN: SIM PIN
AT+CPIN=0000
OK
AT+CLCK="SC",0,"0000"
OK
AT+CPIN?
+CPIN: READY
OK
* the AT COMMAND is represented in RED
* your MODEM RESPONCE is represented in underlined GREEN
Done!