From Naples airport if you would like to use the public transportation services you need to take a taxi or bus to the railway station at Piazza Garibaldi.
Travel time about 30' min by taxi - approximately Euro 30,00.

The most convenient railway station in Naples is that of Napoli Centrale, at Piazza Garibaldi, where on a lower level you can get a Circumvesuviana local train to Sorrento (60' min, ticket fare Euro 6,00).
In Sorrento, close to the station is the bus stop "SITA" for Positano-Praiano-Amalfi (60' min, ticket fare Euro 1,80).

How to reach Positano. Praiano, Furore Amalfi and Ravello from Sorrento
As you have reached Sorrento, you can take the Sita bus to reach the above towns. The Sita bus station is located in front of the exit of Circumvesuviana. Near by there is a magazine shop where you buy the ticket to board the bus. Make sure to have the ticket so you can clip it on the yellow machine in the bus. If you want to know the time schedules of Sita public trasportation, you can check Sita’s web site at www.sitabus.it

In Praiano there is a bus stop at the parking entrance of the Hotel Onda Verde.

Related Web Pages:
Train schedules from Naples to Sorrento

SITA bus schedules from Sorrento to Praiano/Amalfi

Follow this link and fill in the information requested to search for Ferrovie dello Stato (National railways) Rome/Naples - Naples/Rome train arrival and departure times.

Buses from Naples Airport to Sorrento