I've used corrugated cardboard, cotton threads and microbeads for the textures, and Dylusion sprays, and gilding waxes for the colour.
I first spread ivory coloured Powertex over the box canvas, then placed all the elements, using more Powertex as they were added.
I left it overnight before applying any colour.
When dry, everything is quite solid and secure. Powertex do their own sprays, pigments and varnish, but you only need to use them if the item needs to be weatherproof. I'm not likely to put a canvas outside, so I wanted to try the sprays I already had. Decided to use the Dylusion ones, as the colours are so strong and vibrant. I then used some gilding waxes for the highlights, and sprinkled some mica flakes too.