It's easy to make.
Download the model from HERE.
Once you have printed it , glue the model on some cardboard and cut it.
You need a blunted object to score the flaps and the lines for an easy folding.
Once finished you'll have a 7 inches high paper model.
Step 2: Make the wheels.
Just roll the fake treads, score the small flaps and glue them to the sides of the wheels.