Living with your puppy
The top training issues for people with young puppies are toilet training (house training), lead training and teaching the pup not to chew up the house!
The use of a cage/crate can help with 2 of these. A puppy will be very active and always up to mischief. It takes time to teach a puppy what items around the house are fair game for chewing (his own toys) and which are not (your furniture, shoes, electrical wires, kids toys etc). Whilst he is learning you need to watch him every second and that is not always practical. Whenever you are not able to supervise the pup, he can be put in the cage where he cannot do damage to himself or your belongings.
As the pup begins to treat the cage as home/bed, he will be reluctant to wet or soil his sleeping area and this can be used to your advantage. He is less likely to have a toilet training "accident" whilst in his cage (providing you do not leave him there too long) and when you let him out you can take him straight to the garden where he will almost certainly perform immediately!
Whilst cage training has many benefits it cannot be stressed enough that a cage is not a substitute for proper time and training on your part. Leaving a dog or young puppy in a crate for large proportions of the day will not help your long term training and will almost certainly lead to other behavioural problems.
Many cages/crates are available and they are now more affordable than ever. When you buy a cage you need to think ahead. Are you going to use the cage during the early months only and dispense with it as you dog gets older or are you going to use a cage throughout the dog's life. You need to buy a cage that will be big enough for your needs. It needs to be large enough so that the dog can lie down, on its side, with its legs outstretched, without being cramped. It also needs to be tall enough so that the dog can stand up without ducking its head. Think about how large the cage needs to be as the dog grows.
Most cages are designed to fold up which means that you can take it with you if you go travelling. Check out my links page for some links to suppliers of cages. You will find a wide range of prices but beware that some of the very cheap versions may be too flimsy for your needs or may not be well-finished so that there are sharp areas or the design may be flawed, leaving areas that your dog could get caught up on (for this reason it is recommended that your dog should have its collar removed before going into the cage).
Once you have your cage you need to train your puppy/dog to go into it. He needs to volunteer to go in. You can achieve this by placing a toy or treat (or his dinner) in the cage and simply waiting. When he does go in you can praise him and let him come out when he is ready. Only when he is obviously very happy being in the cage should you actually close the door. Even then you should only close the door for a few seconds before letting the dog out again. You can build this up over time and eventually the dog will start to see the cage as a "safe haven". It can become a warm, protective environment where the dog can sleep in peace (away from young children for example). I have always put a treat inside when I want my dogs to go in their cage and they now race me inside when I head for the treat cupboard.
When I have had young puppies I have made one end of the cage the "bed" end with a cosy cardboard box lined with warm bedding. The other end is lined with newspaper. Young puppies are usually unable to wait all night before needing to urinate so they can go on the paper. When the puppy is very young they may cry at night and, whilst your toilet training may be quicker if you get up and let them out, they very quickly realise that they can "summon" you if they cry and it takes much longer to get them to settle at night. By ignoring the crying, they quickly settle and any "accidents" can be easily cleaned up in the morning. As the pup gets older and can "hold" their bladder for longer, the accidents will become fewer and fewer until they become dry at night. As the pup gets bigger, their "bed" end of the cage needs to get bigger too until the bit left for the newspaper is so tiny that he would rather wait to go outside!
When leaving your pup in the cage you must ensure that he has fresh water at all times. There are water bowls available that can be bolted onto the cage so that they do not get tipped over. You should also give your dog something to do in the cage. Give him a selection of toys that will stimulate and tax him. I give my dogs soft toys (which they love), hard toys that are great for cleaning their teeth and satisfying teething aches. I also give interesting toys that the dogs can "work at". I give sterilised bones with the insides smeared with dairylea cheese. The spend hours licking out the cheese. You could also try a "kong" stuffed with treats or a "treat ball" which releases treats as the dog rolls it around. These things will prevent the dog from becoming bored, too dependent on you for entertainment and will help him to learn which things are his.