How do you teach a puppy to sleep on his own?

We put him in his basket in his room downstairs and shut the door and then we go upstairs to our beds. He whimpers and crys for a while and then settles down. He will sometimes wake up again in the night and start crying again. The breeder gave us a 'puppy pack' with instructions when we brought him which said to let him cry and just leave him to sleep on his own. Is this the right thing to do, or not? How would you suggest doing it?