You can go directly to Tung Chung from Kowloon Station (Tung CHung Line) and the ticket fee is 15.5HKD for single trip. Get out of Kowloon mtr station from Exit D2 and walk 20 meters to the bus terminus. Take bus 215X and get off in the next stop (Canton Road). Then walk nearly 300 meters to BP international. If you do not have heavy lugguage, you can just walk to the hotel, for it is only about 1km.