Is there any way i can make my camera bob vertically AND horizontally? (Like shown here: http://youtu.be/PCGydpJXIOg?t=3m7s)
I’ve tried, many times, but it just doesn’t want to work. Please help…
Usually a sine wave is used for that. 
How do you do that?..
Use one cycle (from 0 till 2 pi) as seen here:
You use the value of the sin(x) function to move the camera (or better: a parent object of the camera so it doesn’t interfere with user input) a bit.
The value will always do a smooth transition between 1 and -1 as you can see on the graph.
If you’d use this to change the vertical position of the object, it would smoothly sway up and down.
If you’d use it to change the horizontal position of the object, it would smoothly sway left and right.
If you’d use it to change both, it would smoothly sway diagonally.
If you’d use it to change both, but make sure they’re not synchronized (by having one movement use “x+pi/4” instead of “x” for example), it should give you the desired effect.
I hope you get the idea.