Once you get off your flight there is nothing but an occassional restroom - it is a long walk with a tram and several escalators. If you arrive late, consider the Hong Kong Airport Regal Hotel for your first night. It is next to the parking garage so you can walk there without going outside. Their spa is open until 1 am so you can get the 2 hour jet lag massage then go to bed. Take the express train to your hotel the next morning if you're in Kowloon or Admiralty. There are plenty of taxis ouside the train station.