This is alot simpler than the multitude of photographs I'm going to show you make this look. In each step you have the opportunity to add your own touch to the work. Let's start with a basic spine. Use thick paper for the structure.
Step 1 - A SPINAL CORD
Step 2 - MULTIPLE VERTEBRAE
Cutout different shaped vertebrae. Vary size, and ridges. The basic shape is a heart without a pointed bottom. Add a slit in the bottom of each vertebrae to attach to the spinal cord. Use the slits to attach them to the spine.
Step 3 - DESIGN AND ASSEMBLE A JAW
Your jaw can be sharp like a carnivorous raptor dinosaur, bird or shark. It can also be flat like an herbivore for grinding and chewing. Look at picture of cows, ducks, crocodiles, and bird jaws to get a good idea about your subject.
Step 4 - DESIGNING AND ASSEMBLING A SKULL
Place your jaw next to a piece of paper, and trace out the above view of a skull. Your skull can be pointed with a beak, flat-fronted, however you like. It will need to match with the jaw you've cutout so keep the shape and size in mind. Placing side by side with your drawing paper will help design a good fit. Make sure to include eyeholes and nostrils, and draw a line down the middle to make both sides match; skulls are usually symmetrical in shape.
Step 5 -ATTACH YOUR SKULL AND JAWBONE TO A SPINE
This part is easy if you have a large vertebrae at the top of your spine. If you don't you might want to cut one out. Make two slits in the vertebrae, and place the sides of your jawbone into the slits. Fix it using tape or glue. Your spine should hang down from the spine. You'll have to consruct shoulders next, but let's save that for another day. We have to get started on stamping our papier strips so when we go to mâché our sculpture looks like it has feathers, scales, veins, or whatever it needs! Look for a post about that soon.
Congratulations! You now have a skull and spine skeletal structure for your papier-mâché sculpture.