I don't think this is gonna help you very much, but I'll answer your question.
Well, that RTC has four connections — SDA, SCL, VCC, & GND.
SDA ---> SDA (Analog 4)
SCL ---> SCL (Analog 5)
GND ---> GND
VCC ---> positive voltage (in the photo, he has it connected to 5V*)
*Not knowing the specs on that RTC, I cannot verify that is the correct voltage....or how much current it will draw. I'm only letting you know how it is connected in the photo. Use this information at your own risk. Also, I cannot recommend soldering/attaching anything to your Arduino the way as shown in photo (to bottom of pins on back of Arduino).
If you had trouble figuring out how to connect this, making a cell phone just might be a bit too complex for you at this juncture. I sincerely mean no offense. I would strongly suggest doing some other projects first. Maybe do a few things that use each if the components individually? ....just to get a better idea of how each of them work (and don't work). Things tend to get exponentially more difficult when you start combining different components/shields/etc, and try to get them all to work together. Also, that instructable seems rather lacking in information. It looks more like a "look what I did" rather than a "here's how to do it yourself".
— Just my 2¢.