For some reason, I can't post in the Tarot thread. I seem able to post in other threads. With no other option, here's a new topic to answer the question:

The Emperor's Tarot is a writer's device that can be manipulated and presented in any form the writer wishes, so there's no specific make up of its components. However, there are a few well-considered approaches that might help you:

http://inquisitorminmi.deviantart.com/gallery/

This deviantArt user has had a long-running project to produce images of all the cards in his interpretation of the Tarot. They vary in quality, but are all useful and interesting.

http://www.darkreign40k.com/general-background/the-emperor-s-tarot.html

This is the start of a longer article that I begn but never finished years ago (Dark Reign picked it up from circulations online and were good enough to put my by-line on it when I claimed it as my own). My interpretation here is slightly different to that of InquisitorMinmi at dA. With time, I've come around to his POV somewhat, although I stuck to this version when I wrote "Phobos Worked in Adamant", in the Planetkill anthology, which has quite a long passage about an Astropath interpreting a portentous (but ambiguous) spread of the Emperor's Tarot.

R.