Many thanks to Fiona Sinclair who shared her projects’ photos below:
I enclose photos of two of the boxes that I purchased. I decorated them as Xmas presents.
Two were stained than varnished. One box was painted white.
I used wrapping paper with PVA glue to decorate the insides , finally covering the paper with PVA glue.
I would recommend using a thick wrapping paper, like the flowers, as it is easier to fit and stick, though not so great for wrapping. Thin paper like the map, tears more easily when covered in glue.
My brother took the pictures.
Hope this is of use.