Put the pup in for a few minutes with the door closed. If he misbehaves, try to distract him. Try to leave him in his crate if he is barking, howling, or whining, as you are reinforcing this behavior if you let him out. Instead, try to distract him by making noise, (Shake a tin can full of pennies) and if he quietens for a few seconds, let him out of his cage and praise him or reward with a treat. Gradually extend the amount of time you leave him in his crate. Once he is comfortable in the crate for about a half an hour without making a fuss, then he can be left alone. By crate training in this manner you will teach your pup that he will not get out of his crate by making a fuss and you are rewarding his quiet behavior with praise and attention.