I've been the slow coach on this one...a couple of not very brilliant days :( I guess I can do it - thought I'll try it as a dress rather than a hat:). However, I cant say I really mastered it.  As usual I like to try 'what happens if' and many of my trials of changing a parameter or two  did not yield the expected results. But I didnt take notes so I cant give examples. Positioning the cloud is actually annoying - it's OK following eonite's instructions, and if the cloud is positioned first and everything else added later. But I wanted to put a second cloud in a completely different location, above the mountain, and it wasnt trivial,a bit  like driving blind. So instead I modeled an object (in hexagon)  with a similar shape and textured it with volumetric material, aligned it with the mountain in the x,y direction with the align tool and moved it up, and that's that. The objective was to   see if its worth the effort doing it in the FE.  A cloud has several more paramters I could play with, like feathering and altitude details, but I'm not sure its worth it. I only played with the object-cloud a very short time, so I'm sure it can be improved. (I dont understad why it has such a crisp edge at the bottom though). So the jury is still out. Thanks eonite for the explanations - quite helpful and a fun exercise. If I get around to it I'll make it into a metanode and then it should be easy to combine several shapes in the FE.

"I paint that which comes from the imagination or from dreams, or from an unconscious drive. I photograph the things that I do not wish to paint, the things which already have an existence."
Man Ray, modernist painter
http://artpearl.redbubble.com/