So the water element is there but what needs to be done to make it look like a first person camera is underwater?
add blur affect to the blur effect to the cam would be a good start but how do you tell it to only do it when your underwater?
and then there's the Breath...
I don't know where to begin, can some1 please point me in the right direction?
Underwater tutorial: Kostiantyn Dvornik :: Ideas: Unity world's coolest tutorial about water, girls and sky with FREE assets
you gonna need a trigger on your water object with a script that turns on and off your bluer effect with OnTriigerEnter/OnTriggerExit. Same goes for the breathing sound and if you want to make the player need to go to the surface, you can set a counter to start when you enter the trigger and reset when you exit, other effects as instant death or damage when the air low are easy to figure from there.
http://www.unifycommunity.com/wiki/index.php?title=Ocean_Shader_Project
There is code for detecting the camera’s position and changing the fog level that can be found here:
http://forum.unity3d.com/threads/20222-Water-plane-and-flip-texture.