cloak puzzle

[Orlirva]

http://www.gryph.com/byzantine/cloaks.htm
shows a trapeziod cloak - anyone have experience with this design?
I am having some trouble executing this. An obvious requirement is that it be
large enough at the shoulder/upper chest to entirely wrap around the body with a
few inches spare... lets say 58 inches to accomidate a 43 chest plus the arms.
with the trapazoid closing in at a uniform angle, that unfortunatly means that
at the neck I have perhaps 45 inches...so there is a huge excess of cloth around
the neck. The period pictures show a rather loose arangement with the fibula on
the right shoulder - seems to me I can achieve that loose look and still have
an extra 12 inches I don't know what to do with. I tried to fold it in and pin
it well inside, but this came out bulky and messy... the folded in parts would
unfold and flap out.

also, if I had a tablion (I don't, not yet anyway) I would not be folding back the edges of the cloak, or would I?

-Rick