How to change the oil in a 1999 Mercury Grand Marquis?

How to change the oil in a 1999 Mercury Grand Marquis? I am completely a newby and I am very interested in learning how to change my oil in my 1999 Mercury Grand Marquis which has 99128 miles on it. Every three months I am paying an oil change company approximately $60.00 for an high mileage oil change. Will you please explain in detail in steps from beginning to end the process of changing my vehicles oil for the first time in my life.