More highlights and shadows added with the airbrush ...
and then smeared in with the smear tool. At this point I decided to leave this as it was and move on.
Following the same steps for the front cloth I began painting the rear cloth outline, than on layer below, the cloth fill, then merged the layers.
Using white and a darker blue with a small airbrush, painted in some highlights and shadows and began smearing them together again with the smear tool at about 80% pressure and a brush size of 35 pixels.
