1) Buy a ticking clock. (it thinks that it is it's Momma's heartbeat) Put it in the kennel or box with the puppy.
2) Get a hot water bottle. Fill it with WARM water (not hot), and wrap the bottle with a towel, and lay it in the kennel/box with the puppy. Make sure there is no nipples, because the pup will try and feed off of it. This will give the "security" of it's Mother, and it will lay near it, thinking that the wrapped bottle is it's Mother's belly.
Sometimes a radio with soft music helps as well...