Originally posted by Perfecto
Not the greatest but this might help some.
https://www.youtube.com/watch?v=rw1ChV0DfQw
If you have newer version of Maya, then you won't be able to right click a layer and choose preset. Instead, you will right click a layer and choose attribute. Then once the layer's attributes are open, you will see a presets button in the upper right corner. Right click the presets button and then you will see occlusion, etc.
Sometimes I create a separate render layer for each pass. But most of the time I put objects a,b,c... on a render layer and then add all my passes to that layer. That way I can create another layer for objects d,e,f... and create passes for that layer. It's more complicated so I won't go into it. Just know that render layers are different than render passes and the video I posted is using render layers themselves as the passes.
Edit:
Display Layers = Layers that determine which objects are displayable.
Render Layers = Layers that determine which objects are renderable.
Render Passes = How are the renderable objects going to be rendered