NOTE: Watch this tutorial in HD 720p.

http://www.youtube.com/watch?v=IlQ3o7PaNqM

[1] Investigate the disturbance below deck
Swiftly gear up and prepare to move across the main deck to reach the lower deck.

[2] Destroy the pump control panel to access level 2
Follow the lower deck corridor, and climb the ladder up to the Pump Room Safety System. Guard the room and destroy the pump control panel.

[3] Plant the c4 on level 2
Retrace your steps back down to lower deck, find the Pump Room and follow it down to the level 2 decks. Plant the c4 and stay in range until it arms. When armed, flee from the explosive.

[4] Seal the doors to the zombie nests
One survivor must seal and hold the door (press and hold E, must be against door) while another turns the valve (press and hold E).

[5] Find the hatch access code
Search for the hatch access code below deck.

[6] Enter the code and hold the area
Head to the Hatch System Override room below deck and enter the password using the keypad (press E on the correct numbers).
Guard the hatch System Override room for 40 seconds while the hatch releases.

[7] Hit the hatch release!
After your standoff with the zombies for over half a minute, press the switch to open the hatch.
Jump down the hatch and swim through the large pipes to reach the lifeboats.

[8] Escape to the boats through the pipes!
Swim to a lifeboat and jump in, use the engine a few times to get the motor running.

[9] Safely reach the island and detonate the c4!
Defend your lifeboat until you reach shore.