After going through immigration, you will need to go downstairs to pick up your baggage. There is an escalator or stairway to get downstairs to the baggage pick-up, and airline staff can guide you. After picking up your baggage you will go through a customs check and then move out into the arrival lobby. There are 3 ways to get downtown - train, bus and taxi. In terms of time, trains are the most efficient, but buses go to a wider variety of locations.
Taxis are convenient, but expensive.
If you have a lot of luggage, there are delivery services which will bring your bags to your hotel the next day. These services are available in the arrival lobby. The train is the easiest and most efficient way to get downtown. From the departure lounge there is a well-marked escalator down to the ticketing area. Accessible ticket counters exist.