first off, there IS a layered shader. if you go to the hypergraph (window-->rendering editors-->hypershade) on the left (under create maya nodes) you can create a layered shader right off the bat. secondly, you need to UV map your creation. the easiest way to do this is with 'polygon UVs'-->automatic mapping'... although depending on the complexity of your model you might want to look into other combined methods... i leave the rest to you.