Getting to Bantayan requires a combination of bus and ferry. From Cebu City's North Bus Terminal (not the South terminal), take a bus north towards Hagnaya Wharf — services run regularly and the journey takes two and a half to three hours depending on traffic. From Hagnaya, ferries (both fast craft and slow boat) run to Santa Fe on Bantayan Island; the fast boat takes about 30 minutes and the slow boat around 45 minutes. Ferries run roughly every hour during daylight, with the last departures in the late afternoon.
The total journey from Cebu City takes three and a half to four and a half hours depending on connections. There is no airport on the island. During Holy Week (the week before Easter), the island fills with Filipino vacationers and ferries can be extremely crowded; book early or avoid this period entirely if crowds are not your thing.