Used a 10k POT to control the 3 wire Vex servo. The two end pins of the POT went to 5V and ground. The middle connection of the POT was connected to the analog in 0 (A0). The servo was connected to the 5V (red), ground (black) and digital pin 9 (D9, white). Used the knob example from the Arduino.cc website to program the board. I was also able to print the Analog value of the POT by using the code from the AnalogReadSerial example.

This can be used for steering mechanism.