I am not sure if the card order of the thoth has some major purpose or not. Hell I do not even remember the original order at this point.
Yes it has a purpose and it is to be a teaching tool
. Also I see more than ONE order possible ... IMO it is rare to find ONE only order or purpose that is right for all situations (except in religion
)
Here are some I worked with ... I would find a big space and lay them out for contemplation ... or set the deck up in an order and draw the cards in order and look at them.
Tree of Life ; deal out Ace to 10 of Wands in the pattern of the Tree of Life, then overlay with the cups suit, then swords and pentacles. Lay the Majors on the paths between the numbers. Or do 1 suit on the Tree and the Majors on the paths, then pick up that suit and lay down the next one (while the majors stay there). Then add piles of the courts, in various positions (as Aeon pointed out above ... and other ways).
The Majors; lay them out via number, astrological order, planetary order .... later (if you really want to do your head in ) you can try constellational order and add the courts that relate to off ecliptic constellations (and The Universe seems a good fit for Ophiuchus ).
The Minors can be laid out in a wheel, positions 'in order' according to their astrological decanate position, but that is just 2 - 10 of each suit.
In the G.D. Book T there is the scheme mentioned above, but also in their writings; 'The Tree of Life Projected into a Sphere' - but that is bound to lead to trouble without certain basic understandings that might not be apparent at first ... and it appears faulty as a system to order cards by.
Or you could go the 'whole hog' and lay out your whole deck in a map of 'Life, the Universe and Everything' @
http://www.tarotforum.net/showthread.php?t=124078&highlight=astro+layout 'Astro Tarot Spread'. - Note; not a 'reading' spread ... a way of ordering and laying out all the cards, for meditation and comprehension.)
And lastly (when you decide to go really nuts) you can cut the borders off and fit the cards together in that big painting Freida did .... before she cut it up into 78 little pictures