Betty, I just printed out the email receipt after paying.

Cheron, Here's the website . From the information I received, it's an easy pick up near the Meeting Point, which is situated on ground floor at arrivals, next to the Travellers Services Desk, this is where our representative will be to meet you. Please look for KST Sydney Airporter buses with distinctive Sydney Airporter Logo and KST representative wearing an approved KST Sydney Airporter ID card.