Puppies generally need enclosed small places to feel secure. Crating works because the pup feels safe in his own private place. Some think that crating is like placing the pup in jail. In this instance, you should never use the crate to administer punishment.
Make sure the size of the crate is comparable to the dog. It is fine to get a larger crate if the dog will grow into it. Use a partition board to keep the crate smaller until the pup grows. Make sure the animal has enough room to lie down, turn around, and stand up comfortably.
Introduce him to the crate first. Let him explore around it. He may go in or just sniff around it at first. He will slowly become at ease with the structure. Begin by placing the pup in the crate for 20 minutes at a time. If he starts to whine, you should ignore it. Placing a cover over top of the cage also helps. It makes the crate seem more confined. You can also put a toy or blanket inside with him.
After twenty minutes, take him out of the crate and then straight outside to potty. Praise him if he does. Take him back inside afterward, and play with him for about half an hour. Then place him back in the crate again. If he doesn’t go in, throw a treat inside. Praise when he enters and close the door. Try another twenty minutes. Puppies can be confined for one hour for each month old they are plus one hour. If your puppy is four months old, he should be able to build up to five hours.
Never leave puppies in the crate for longer than eight hours. They need to be let out at regular intervals to exercise and potty. Following a schedule is the best way for a new puppy. He will come to learn what is expected and comply with minimal fuss.