City Flyer A10 by Citybus
The easiest way to go to the airport directly is to take No. A10 airport express provided by Citybus on Catchick Street.
It takes $48 for a one-way trip, and if you pay by octopus, the return trip will be $24 within the same day.
Airport Express by MTR
You can take Airport Express from Central MTR station to the airport in only 24 minutes. One-way trip costs $100 while a round trip costs $180.
More information about Airport Express can be found here.