How do you change transmission fluid of 99 Porsche 996?

To change the Transmission Fluid on a 1999 Porsche 996, start by lifting the vehicle and securing it on jack stands. Remove the transmission's drain plug and allow the old fluid to drain completely. Replace the drain plug, then remove the fill plug and use a pump to add new transmission fluid until it reaches the correct level. Finally, replace the fill plug, start the engine, and cycle through the gears to ensure proper distribution of the new fluid.