On Tutuila: The island is about 30 kilometres long and narrow, with one main road running most of its length.
Aiga buses — brightly painted family-owned minibuses — are cheap and lively. Fares are around $1 per ride, $0.25 for children. They run between villages and the central market in Fagatogo from early morning until around 5pm, Monday to Saturday. There is no fixed schedule; flag one down from the roadside. Service on Sundays is minimal. Note that there's no direct service from one end of the island to the other — most routes converge on Fagatogo, where you'll need to change.
Taxis operate on Tutuila with government-regulated fares displayed in the vehicle. They're a reasonable option for evening travel or getting to the airport.
Car rental is available in Pago Pago and at the airport. Avis, Tautai, and a few local operators rent cars. You drive on the right, as in the US. Speed limits are low — 25 mph (40 km/h) on open roads and lower through villages. A valid driving licence from your home country is accepted; an international driving permit is technically required for stays over 30 days.
Between islands: Samoa Airways connects Tutuila with Ofu and Ta'u in the Manu'a group. Flights take about 30 minutes but schedules are limited and cancellations due to weather are common. An inter-island ferry also serves the Manu'a Islands, though it runs infrequently. A small boat makes short runs to Aunu'u Island off Tutuila's eastern tip.
If you're planning to visit the outer islands, build flexibility into your plans — connections can be unpredictable.