If you reserve in advance Happy Gecko can organize a pick-up from the mainland for you. You will be picked-up at Tongkeina or Bahowo village (depending on the tide) which is about 12 kilometers north of Manado. From there It will take approximately 20 minutes by boat to reach Bunaken. You can also be picked up at the airport or any other place in or around Manado. For safety reasons Happy Gecko does not make boat transfers to Bunaken in the dark. Make sure your flight arrives before 4.30 p.m. otherwise you will need to stay overnight in Manado.
A cheaper and more adventurous option is a transfer with the public boat. Every day (except for Sundays) around 2 pm at least three boats leave for Bunaken from Dermaga Wisata Kalimas in Manado. It costs Rp 50.000 per person and takes almost one hour. You will unboard at Bunaken village and find yourself an ojek - a motorbike with a driver - who can drop you off at the resort. On Monday, Thursday and Saturday there is a public boat service that stops in front of Happy Gecko. The name of this boat is Siloam and leaves at about the same as the other public boats from the Jengki river right next to the Berserhati market in Manado.
Manado has an international airport. Singapore Airlines owned budget airline Scoot flies from Singapore to Manado three times a week and vice versa. Besides the above there are many daily flights to and from Jakarta, Bali, Surabaya, Makassar and other places in Indonesia. For domestic flight information, check the websites of for example Garuda Airlines and Lion Air. Good websites to book domestic flights online and compare prices are www.tiket.com and www.nusatrip.com.
The center / port of Manado is about a 30 minute drive from the airport. Taxi's are plentiful and reliable and should cost you no more than Rp 100.000.
You need a visa to enter Indonesia. Visitors from most countries will buy a 30-day Visa-on-Arrival at Indonesia's international airports. Your passport must be valid for at least six more months and you may be asked to show a return ticket. Make sure you check the latest visa regulations before departure.