You do not have to book a resort. Guesthouses on inhabited local islands put you on the same water for a fraction of the cost, and the ferry network between them is the trip.
One night to catch the rhythm of the country and the fish market. Most transfers leave from here anyway.
Onward: Speedboat or public ferry, 30 min or 2 hr. To Maafushi
The most developed local island: dive shops, sandbank trips and a designated bikini beach. A good introduction.
Onward: Speedboat, 2 hr 30. South to Dhigurah, via Malé or direct
A three-kilometre sand spit in South Ari Atoll, where whale sharks are in the water all year. The main reason to come this far.
Onward: Ferry, 1 hr. To a neighbouring island in the same atoll
Fulidhoo is tiny, quiet and full of stingrays at dusk. Or split the difference and finish with one night on a resort island.
On six nights, Maafushi and Dhigurah alone. Do not try to add a third island.
Add a two-night liveaboard dive boat, which reaches atolls the ferries do not serve.
Planning around the public ferries without checking the timetable. They are cheap and slow, they do not run on Fridays, and many routes go only two or three days a week. Getting the days wrong can cost you two nights in Malé waiting for a boat.
Read the full Maldives travel guide or take the Maldives packing list.