Right click on the file you have downloaded and select Extract All from the list that appears.
Select a suitable location and make sure the Show extracted files when complete box is ticked.
Click the Extract button and when the extracted contents of the zip file appear, copy the aircraft folder into your X-Plane 11 aircraft folder.
Launch X-Plane 11 and start a flight using the aircraft.
An activation window will appear, prompting you to enter your serial number. Paste the serial number found above and click the Activate button.
After a short pause, a message will appear informing you that the product has successfully activated.
From the top menu bar, select Developer > Reload Current Aircraft and Art
The aircraft is now ready to fly.