Please do not go into the city any other way, traffic is horrible, airport express is practical, clean, fast,... no way to get anu-y quicker to your destination. It is extremely well indicated at the airport, you cannot miss... tickets can be bought everywhere or up front.
I really enjoyed this trip. I found the juxtaposition of the Portuguese architecture and 'Las Vegas' fascinating. After we were shown the Casino we were left to explore by ourselves. I would have preferred more of a guided tour round the other Portuguese buildings.
Great way to get to hotel via the free bus! You cant get lost once you step off the train, plenty of staff to guide you through to the bus pickup. Find your hotel on the published list and take the bus. Very easy and quick way to get into the city.