In level 2, "Toy store," go into the ruins room. Jump on the trampoline and jump 
to the ledge. Jump to the other ledge that is close to the other one. Walk all the
way around until you see a hole in the floor. Go to the edge of the ledge and jump
onto a platform. It will have a doggie point (extra four tries) on it. Wait for 
the train. When it arrives, get on.