Serial Port Trouble with Arduino Nano (Mac OS X Yosemite)

When I plug in my Arduino Nano v3, it resumes the previous program that I had done on a previous Mac in my university. However, when trying to select the serial port of my Mac laptop, the port isn't available.

This is my first time installing the Arduino Software on my laptop as the software was readily available in the university.

I have selected the Board and Processor as Nano & ATmega328 but this hasn't made a difference.

I have read through the troubleshoot and support, I'm guessing that I have to install some FTMI drivers but I'm unsure which ones to install.

I'm struggling to sort out the solution with the Troubleshoot & Support in relation to using it with a Mac Computer. I was wondering if anyone had the same trouble or if someone has the solution to this?