Park in one of the arrivals bays and head to reception to check in. You should have a copy of your booking confirmation with you. You'll need to leave your keys with reception, as your car will be parked for you. You'll be given a ticket, which you should keep safe as you'll need it when you return. Then just wait for the shuttle bus to the airport in the waiting area. You'll need to show your ticket to the driver. If you have sports equipment or lots of luggage, you may need to wait for a bus with more space during busy times, so make sure you leave yourself plenty of time to get to the airport.
Just catch the shuttle bus back to the car park from bus stop A - the same place that you were dropped off at. You'll need to show the ticket you were given when you checked in to the driver. After you've collected your keys from reception, just drive to the exit barrier, and scan the barcode attached to your keys to get out. If you lose your ticket, you'll need to answer some security questions and show a photo ID, so make sure you have one. If you return early, you will need to contact the car park directly to give them as much notice as possible. If you don't, there may be a delay before you get your car back. We can't offer you a refund for any booked parking that you don't use.