Angaur is one of the harder Palauan islands to reach. Light aircraft fly between Koror and Angaur a few times a week — schedules slip and flights are routinely cancelled for weather or low bookings. The flight takes about 30 minutes and gives spectacular views down the Rock Islands chain.
The alternative is the supply boat, which runs irregularly from Koror and takes most of a day in open water. Charters can be arranged with dive operators but they are expensive. Plan to stay at least two or three nights — turning up for a day trip is rarely possible.