Decide on your color scheme ( you could go bright and whimsical with this too). I painted my plain boxes black, let dry, then painted a layer of white school glue ( plain old white glue) over the black paint. Let almost dry and then went over that with white paint. Oooohhhh crackle crackle.
Ann at Make The Best of Things has a great tutorial here.
I traced around my boxes on the back side of the scrapbook paper I chose ( Recollections Spider Web) and cut out tops and bottoms for my boxes. Mod Podged those on using MP Matte Formula ( my go to).
While everything was drying, I grabbed a Bag O Skulls. Literally:
I picked these up last year at either Dollar Tree or Michaels or Target or somewhere I was scrounging around after season. I debated whether to leave them the color they were or paint. Went with paint.
Used Martha Stewart Craft paint….that stuff sticks to anything including cheap plastic skulls. Went over that with Martha Stewart glitter paint in sterling.
Total cost: $3 (if that)
If you want to see another great coffin box idea, check out this one from Sarah at Alderberry Hill: A Glitzy Halloween Coffin