Which bus from Hong Kong airport to Butterfly on Prat Hotel (Prat Rd - TST area) & return bus back to airport?

From Hong Kong Airport, you could take bus A21 and get off at Cameron Road, Nathan Road. Then, you could walk along Cameron Road and turn to right at Carnarvon Road, then turn to left at Prat Ave where the hotel is located.
When return to the airport, you could walk along the Prat Ave and turn to right at Chatham Road South. Then, walk down to the cross of Chatham Road South and Mody Road, where you could take bus A21 back to Hong Kong Airport.
Ps: you could use google map to get the route in advance.