The painting technique used was the true fresco method, 'fresco' is an Italian word merely meaning 'fresh'. That is, the painting was carried out on plaster that had set but was not yet dry.
Careful exmination of the painting has revealed a number of distinct stages in its creation.
The incision of vertical and horizontal layout lines.
The execution of a preparatory drawing in a dark earth colour.
The laying down of areas of cinnabar, which were then polished.
The painting of shadow and mid-tone details in various shades of brown.
The addition of highlights and details in an impasto technique.
Laying down of areas of blue frit.
Painting the garlands and laying down areas of dark green paint between the columns of the pavilion.
* Roman Painting: Roger Ling 1991, pp.198-204. A particularly fine group of plasterers' tools, recovered from a well in the Saalburg Roman fort in Germany, are shown on page 200.