How do you get to a new city on gta4 ps3?

1. Complete the first mission. This will unlock the ability to travel between Alderney and Bohan.

2. Go to the nearest subway station. There are stations in each of the three boroughs.

3. Buy a ticket to the desired borough. The cost of a ticket is $5.

4. Board the train. The train will take you to the desired borough.

5. Get off the train at the desired station.

You can also travel between boroughs by taking a taxi or by driving your own car. However, taking the subway is the most convenient and affordable way to travel.