1) Take a flight to Dumaguete 2) Take a bus from the airport to Malatapay, Zamboanguita (this is where the bangkas leave for Apo island) Alternately, ask your hotel to arrange the transport. The latter is far more convenient.
Boat rental (2 way)it doesn't matter if you stay in the island for a day or a week. The rates are the same. 2000 pesos - small boat max 5 pax 3000 pesos - big boat max 10 pax Solo travellers may also join other boats for 300 pesos.
There is a counter at Zamboanguita pier, where you pay the environmental fee.They arrange the boat for you.
Warning : You HAVE to walk through the water to board the boat. So remember to change into your slippers (the water is stony) and either wear shorts or roll up your clothes.
The boats do not have any curtains on the sides, so assume that you will be wet within minutes of leaving. Dress accordingly a, be ready to be wet, and keep all your belongings (especially camera, money and documents) in your bag. The boatman will keep your bags inside the boat in the bottom, so it is more safer.
You must arrange for transport from one of the local boats to come and retrieve you for a fee. It is a several mile trip in an outrigger canoe with outboard motor over open water, swells can be large and you can expect to be sprayed with saltwater throughout the trip (wear sunglasses). The boats will generally meet you at Zamboanguita where the Malatapay Wednesday market is held. Take a jeepney from Dumagete, just ask the driver or the guy who collects fees off the back of the jeepny to warn you when it is your stop. It can also be arranged through Apo Island Resort to go from Dumaguete to Malatapay-Dauin, and from there directly to the island.
If you want to stay near the pier in Dumagete, the Coco Grande Hotel is only 1 minute away. There are many similar htoels liek Liquid Dive located neither closeby nor far away from this jetty. There are 4 lodges in Apo island itself. While their rooms are sparse, they do not have any electricity at night (and for many hours during the day)
Details of the island can be found here - http://expattraveller.blogspot.com/
The island is only 3 km around and 120 m high at the top of the hill, however, it is hilly.
You can walk upto the lagoon and the coral beach on the south eastern coast (through Apo village)
A steep set of stairs takes you up the hill - to the lighthouse (30 minutes trek, medium difficulty). Not marked - ask the staff at Liberty lodge for the way.
There are a number of other treks in and around the island - they can be found listed here - http://visitapoisland.blogspot.com/
One of the Philippines' famous diving sites, Apo Island has one of the world's best known community-organized marine sanctuaries. It is home to over 650 documented species of fish and estimated to have over 400 species of corals.
Diving and snorkeling are the main activities around the island. Resorts on and off the island typically hold diving programs for different skill levels. Instructors are commonly PADI-certified. The diving is excellent, plenty of reefs, tons of fish and turtles-amazing visibility. Keep an eye out for the Giant Trevally which is known in these waters.
There are 2 dive shops in Apo Island: 1. Apo Island resort - USD 25 inclusive of complete gear, boat and divemaste; USD 20 exclusive of gear, inclusive of tank & weights, boat and divemaster. Less USD 2 for shore dives.
2. Paul's diveshop - Php 1150 for one dive, P2200 for 2 dives exclusive of gear. For complete gear, add Php 280 per dive.
Conservation tax of P300 is charged if diving within the sanctuary and P200 if diving outside of the sanctuary
These rates are as of June 2009
There isn't much in the way of retail on Apo Island. It is advisable to bring anything that you may need with you because it is a long trip back to Dumagete. The local women will try to sell you t-shirts and sarongs when you arrive and when you leave.
Both resorts have Apo Island t-shirts and hats which are little more than the words Apo Island and the symbol for divers.
Both hotels have restaurants, Liberty's has particularly good chocolate/banana shakes. Menus are limited but what is available is pretty good. At Liberty's, the dive master will go table to table during dinner and help you arrange the next day's dives.
Several beach resorts at nearby towns regularly offer trips to the island, and it is more common among divers and tourists to get accommodations off Apo Island. Examples of hotels and resorts outside Apo Island are Liquid Dive Resort , Playa de Malatapay Resort and Restaurant (www.playademalatapay.com) and Thalatta Beach & Dive Resort in Maluay Zamboangita ( www.thalattaresort.com ), Bahura Resort & Spa  in Dauin and Wellbeach Dive Resort in Maluay  . Rates span from budget to splurge, with some hotels usually offering a range of activities that explore the mountains, water falls, sulfur springs and other beaches of Negros Oriental.
There are only two resorts on the island, Liberty Community lodge and Apo Island Beach Resort.
Liberty Community Lodge  is the larger of the two, it has a very nice restaurant and both private and dorm type rooms. The private rooms are situated in what appears to be a large expensive private house, the showers use barely desalinated water and the island is always on restricted water use.
Apo Island Beach Resort is on the opposite side of the boulder from Liberty Community Lodge.
Apo island is generally the place to get out too, Dumagete is the city to get to Apo from. Here  is a good write up on the island.