Draping the chiton

[Giannis K. Hoplite]

The difficulty in reconstructing Greek clothing is in finding the correct materials and decoration. Even archaeologically Greek textiles have been proven to be very difficult to reconstruct, due to their laborious means of construction, mainly very thin wool threads and fine weaving. 

The result we see in paintings and sculpture was achieved by a multitude of techniques, some of them almost extinct. They included weaving with different thickness or different material yarn to create patterns, twisting threads to create a pleated effect, and treating with oil to create "shiny" fabrics. 

Decoration could be even more elaborate and complicated.

In other words, I would never say that Greek clothing was simple or easy to reconstruct. Perhaps their fashion was towards garments of simple shape, but intricate in their materials and their properties.
Your chiton may look bulky, but it doesn't necessarily mean that it is too wide. It probably means your material is a bit too thick or stiff, and/or it is too long.

Khaire 
Giannis