Getting There & Away
The easiest way to arrive is by speedboat from Valença (accessible from Salvador by a combination of ferry and bus via Bom Despacho.) From Valença's ferry dock, catch a speedboat (R$44, one hour, five departures between 10am and 4pm on weekdays, reduced service on weekends) to Boipeba. There are other options between Valença and Boipeba, including a bus–boat combination via Torrinha, but the direct speedboat is easier to plan. Accommodations owners in Boipeba are helpful resources as you're planning your travel strategy to or from the island.
If you're arriving from Morro de São Paulo you can ask the travel agencies there about hitching a ride on one of their tours of the island and you may even be able to negotiate a lower price for a one-way trip if their tour is light on people. Keep in mind that in the off season the tours may be more sporadic. Some companies also offer a 4x4 tour to Boipeba, but they are more expensive (R$95–110).
Check www.boipebatur.com.br for more details on these and other transportation options.