What's the best transport transfer going to Holiday Inn Causeway Bay from HKIA?

Well, you may take bus line A11 from Airport (Ground Transport Center) to Wan Chai Fire Station. Afterwards, walk south for about 200 yards, and you will see the hotel. The bus line A11 operates until 00:30, and it costs CNY 40 per person.

If you cannot catch the last bus, you may take Night Bus Line N11 from Airport (Ground Transport Center) to Elizabeth House Station, and you can see the hotel to your opposite. The bus operates from 00:50 to 04:50, and the fare is HKD 31.

Also, you may take a taxi to the hotel directly for about HKD 285. :)