Okay here is a simple step by step:
Get in your car, put your seat belt on and close the door as if you are ready to drive. Do not insert key.
With your free hand, press the odometer button and keep pressing it.
insert key and turn once - its called the accessory position of the key
Remember you have to keep pressing the button throughout, the service light will start to flash.
the word reset will appear, release button and press it again once and keep pressing it.
release button when you see green lights appear ... this means the system has been reset.