Crate Training A Puppy
  Puppies need constant supervision during the first 
  few months. To begin puppy training, place a treat
  in the crate. Allow the puppy to enter the crate on
  his own. Dogs learn best when they are rewarded
  for positive behavior. Repeat this procedure several






  times.

  Another suggestion is to feed the puppy in the
  crate as a method of introduction. Make the crate
  comfortable. Place a soft old blanket or pillow in
  the crate. Place a few of his favorite, safe toys in
  the crate. Dogs will be reluctant to soil in an area
  that they recognize as their bed or den area.

  Make sure you take your dog outside before confining him to the crate. When the puppy
  seems comfortable lying down and has adjusted to the crate, close the door for a minute
  or two. Stay nearby. If the puppy whines, wait until he stops, and then let him out of the
  crate. When you open the crate door, ignore the puppy for a few minutes so that he does
  not associate coming out of the crate with receiving attention. A puppy can injure himself
  if he is uncomfortable in a crate and left unsupervised.

  Crate Training An Older Dog
  Although it may be harder than training a puppy, using a crate for dog training can be
  done by rewarding the older dog the same way. Follow the same steps for puppy training.
  It is essential an adult dog be supervised carefully while he is introduced to the crate.
  Some dogs adjust more rapidly than others. An adult dog can injure himself if he is
  uncomfortable in a crate and left unsupervised. 

  Length Of Time A Dog Should Be In The Crate
  It is recommended during the puppy training process, that the puppy should be in the
  crate a maximum of 1 hour per month of age. Once he is trained, do not leave the puppy
  in the crate more than 4 hours. For dog training, an adult dog (1 year of age) should be in
  the crate no longer than 8 hours at one time.

  Size Of A Dog Crate
  The crate length should be 1½ times the length of your dog when full grown. Your dog
  should be able to stand up, turn around and lie down in the crate comfortably. If you are
  purchasing the crate for a puppy, place something indestructible, like plywood, in the
  crate to act as a partition. Place the partition so that the puppy has 1½ times his length
  to move around in the crate. As the puppy grows, move the partition to accommodate the
  growth. The partition will keep him from soiling in the crate’s excess space.   Below is a
  guide to use when choosing the correct size crate for your dog.