See ghost fishes, pirates and Seemonsters
I used 6mm MDF wood panels, and glued and screwed them together.
The cover has 4 big holes, for aeration.
First, I painted the inside of the box black
On the outside I glued half wooden balls to make it look like rivets.
With wooden spatula I made the surface rougher. I used wood glue to write the text on the front. Now let it dry for min. 24 hours. Then I painted the outside black and again I had to wait for 12 hours.
I used copper color and a soft cloth to make it look like an old box made of copper. In the aeration holes I glued fly screen pieces.