You will need:
blank boxes
plastic animals
craft paint or spray paint
paint brush
super glue

Choose animals that sit flat on the box. Some work well with two feet, but usually it is best to use four feet that are flat. Lay out all of your lids and animals outside on a board or sheet. Spray with two even light coats, letting dry between the coats. For the animals, you will let one side dry, flip and spray the other side. Feel free to paint the bottoms to match, too. I chose navy boxes so I could use the base as another color, with less work.
Once dry, pour out a small spot of paint on a dish and start painting the animals on the bottom. Flip and paint the tops of the animals. Paint the tops of the boxes. Let dry and repeat a coat or two for even coverage. Let dry.

Add a small drop of glue to the bottoms of each of the feet. Press onto the box top and hold for 30 seconds (or according to the directions on the glue.) Repeat for remaining boxes.  Let dry and paint over any visible glue if necessary.