Make sure you have the fob present, then turn the ignition to ign, then off, then ign, then off, then ign (ign 3 times). Quickly press the left turn signal 3 times. Press the right turn signal 1 time. Your signals should flash 3 times and the factory pin should appear in the odometer and the first digit (1) should be flashing. Now use the left turn signal to change the number from a 1 to the number of your choice, then use the right turn signal to "store" that number and move on to the next digit.
Summary: Ign 3 times, left 3 times, right 1 time. Then left to change, right to store.
Using the pin to disarm the system is different of course.
Turn to ign, then quickly press and hold both turn signals until confirmation (odometer changes to

Hope this helps.