First off, let me start out with this: Dogs in the wild never lived in houses or had crates; they did not have to worry about pottying in doors or getting in trouble for doing so. They did however have dens which a crate resembles. I am a strong believer in crate training. Think back to "den days", when dogs lived in dens; they did not use the restroom inside their “home”. Instead, the dog went outside and away from the den to relieve himself. Dogs do not like to potty where they sleep unless forced to (if left kenneled too long or too big of a kennel). Being in a crate and having to go outside to do business is natural for a dog and with proper training, this can easily be established in the home. I have had a ton of success with crate training. Not only does this help with potty training, but will also minimize boredom chewing, and works great in emergency situations. When you first get your puppy, go and get her a crate. My number one advice on this is: do NOT get one too big. You want one in which she can turn around in, lie down in, and stand comfortably but NO larger (she should not be able to pace in the crate). The larger the crate, the harder it is to succeed at potty training inside the crate. I prefer the open air wired kennels for training only because you can get a large one with a divider to make the kennel smaller in the beginning and it can grow with your puppy (Midwest brand is a good one that makes the divider: check Walmart).
Also, dogs like a dark kennel to represent a den. In the beginning, I suggest to put a dark blanket over it at all times and they can go in and out when not confined to it- you may even decide to continue to keep it covered, depending on your dog. When confined to her crate at night, leave her alone and completely cover it. NEVER open the kennel or talk to the puppy if she is crying or remove the blanket to look at her unless you think it is an emergency. This would be giving her attention while she is crying and you will only be rewarding the behavior and she will learn to be noisy to get her way.
Another HUGE no-no is to ever reach in after your puppy while she is in her crate especially if she retreated to it because she was reprimanded or in trouble for something or if she went in on her own. Let her come out on her own. Remember this is her den and not yours and the moment you "trespass" into her home (maybe by putting your hand in or trying to pull her out) you could lose her trust and be seen as a predator. I suggest putting your puppy in her crate at night, when you must leave, or in times of assigned "quiet time". I never advise someone to put a dog in her crate to reprimand her. The crate is a happy comfortable place and not to be used as punishment (perhaps when in trouble, you may want to use the command “outside” and put the puppy outside by herself). When the puppy isn’t in the crate, keep the door open so she can always go in at her free will. To start training for the crate, first coax your puppy into the crate while saying "kennel" or "crate" (only pick one of these commands, do not use them interchangeably- this will become the command you will use to tell your puppy it is time to be quiet and go to her den). Coax her with either a treat or happy sounding voice cues. If your puppy happily and on her own will goes into the crate, rewarding is essential. Either reward with food/treat by tossing it in or use verbal praise but don't reach in the crate to pet her. If your puppy isn't going in on her own, you can place her into the crate gently. Do not shove or forcefully put the puppy inside, this only takes away trust. Once she is in her crate, close the door, cover the crate, and walk away. Do not go to the crate when the puppy is whining or complaining. Only open it when he or she has been quiet for at least five minutes or when you want her to come out once she is quiet. If leaving your puppy alone to cry becomes too difficult for you, try putting her crate in a room away from where you will be, as discussed in a couple paragraphs. A blanket or towel can be placed inside but it may make it harder on the dog to not potty inside the crate. I personally do not put anything inside the crate until the dog is completely potty trained in the house. I also choose a designated place for the crate for the first few weeks and I try to not move it during the training time.
Due to puppies whining the first few times in the crate, I put it in a place away from my bedroom so I don't have to hear it and so I don't get tempted to check on the pup during the night- but I do keep it in an active room such as the kitchen or living room so they are a part of the family. Also remember that any puppy has a small bladder and it may be hard on it to be in the crate all night. If you have gotten a puppy from me, she should be used to sleeping in the crate from 11pm to 5am and during the day for no more than periods of an hour or two while I cannot monitor her. Remember that anytime you leave your home, and anytime you need to be alone, your puppy should go in the crate. Generally, I crate my puppies any time I leave the house until they are around six months or even a year, and at least until one hundred percent potty trained.
Crate training is essential, to me anyways, to aid with potty training (see potty training article). As SOON AS you take your puppy out of her crate take her immediately to your yard or desired potty area. Your puppy, as soon as she wakes up, will immediately need to go to the restroom and will associate your yard to the designated potty place if not allowed to accidently potty inside when she comes out of her crate.