By far the most economical means of travelling into New York centre from JFK airport is by train. The density of traffic in the city can make a journey by bus or taxi painfully slow and expensive the closer you get to the centre.
Most people coming from Britain will arrive at JFK Terminal 7. There is a free bus to take you from there to the relevant stop on the JFK Airtrain, where you buy a $5 ticket to take you to Jamaica Station or Howard Beach Station. The Airtrain is a bit like London's Circle Line, i.e. it goes round and round, so check that you are going in the right direction. You'll get to Jamaica Station or Howard Beach eventually but it saves time to go the right way. At Jamaica or Howard Beach Station buy a ticket (machines or booth) and take the Long Island Rail Road (LIRR) into Manhattan, from where you can take the New York Subway to all parts of the city. Buy a one, two or seven day Metrocard at the Subway station and you'll save money on single trips, both on the subway and buses.
JFK Airport, Long Island Rail Road (LIRR), New York Subway www.mta.info
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