Cardboard Automata (plural of automaton) are hand-powered mechanical contraptions that are made of cardboard and other craft materials. They usually create an animated scene that is fun to look at.
This shows how to paint and clean up properly.
All about different types of cams and followers
Using different materials to make automata (including upcycled materials and...food!)
507 Mechanical Movements: A visual encyclopedia of different mechanisms
Rob Ives's Milk Carton Elephant
Wolf Cat's Web page: 29 wire automata in 29 days
Here are a few animations of some of the mechanisms that you might use in your automaton. Even if you don't, they will get you thinking: