Help with Camera Bobbing / Camera Manipulation?

I'm making a game which involves Camera Bobbing. Basically Camera Manipulation, but I can't get the script to work. You might notice it is used in horror games for creepy effect. Here is an example game made by tyridge77: http://www.roblox.com/GCC-Confined-a-Story-of-Death-and-Shadows-place?id=177966109 (The camera moves up and down in the game)

Anyone know how you could help me with this?