I'm trying to create a realistic coffee cup.

1) I found a "coffee" shader at highend3d, but actually it consist of two different shaders - how do I mix these together?

2) Besides that, I would like to create some damp (smoke) from the hot coffee to make it even more realistic. Which way should i do that?

I attach an image of the cup as it is now - rendered with mental ray - final gather.