Jia and Jason handled most of the fabrication, while I wrote most of the code to handle the GSM module's interaction with the Arduino. We used a software serial connection to communicate with the module, and used a series of basic commands to initiate the sending of an SMS message when one of the black symbols is squeezed by the user's fingers.
One of the key things to remember is to send the AT+CMGF=1 command anytime the GSM module has restarted. This command sets the module's SMS mode to text, allowing the subsequent command to send the message, AT+CMGS, to function properly. If you don't do this, you will be unable to send messages at all.