SITA buses depart hourly from Sorrento’s Circumvesuviana train station.
Follow the SS145 west from Sorrento for about 7km until you see signs off to the right.
There is generally street parking available, although August can be busy, especially in the evening.
It's a 4km walk from Sorrento to Sant'Agata, mostly uphill, on good paths with steps. From Piazza Tasso in Sorrento, venture south along Viale Caruso and Via Fuorimura to pick up the Circumpiso footpath, marked in green on the walking maps available from tourist offices. The walk should take approximately one hour.