Hi, how can I buy ticket? And which ticket sh ould I buy? "Airport to tsimShaTsui Chungking mansion"

According to your travel plan, you are suggested to buy HK Airport Express Travel Pass. This card contains one or two Airport Express single journey(s) plus 3 consecutive days of unlimited travel on MTR. The concrete transportation information as follows:
1. Take airport shuttle bus no. A21 at Airport (Ground Transportation Centre), and get off at Middle Road, Nathan Road. Then walk to your hotel. It will take around 70 mins on the way.

2. Take West Rail Line to Nam Cheong Station and then take Tung Chung Line to Sunny Bay Station. Transfer to Disneyland Resort Line to Disneyland Resort Station, Exit A.

3. Take Disneyland Resort to Sunny Bay Station and then take Tung Chung Line to Lai King Station. Then transfer to Tsuen Wan Line to Mong Kok Station, Exit D3.

4. Take bus no.2 at Ngong Ping Bus Terminus, and get off at Mui Wo Bus Terminus. Then take ferry at Mui Wo Ferry Pier, and get off at Central Pier No. 6. After that, take public bus no.70 at Central (Exchange Square), and get off at Aberdeen Tunnel Toll Plaza.

5. Take public bus no.1 at The Peak( Public Transport Terminus), and get off at Pedder Street, near MTR exit. Then walk to HK Station. After that, take airport express to the airport directly.