Crate training is where your dog is put in its crate and left in there until its time to go to the bathroom. The dog is let out and expected to use the bathroom. If the dog goes, they get free time and if it doesn't go, they go back in their crate for about another half an hour. Then they are taken to the bathroom to try again. This process is repeated throughout the day with planned meals in between. Some people do it slightly different but it is really all the same as long as the dog is getting free time. Dogs shouldn't eliminate in their personal space, so they won't use the bathroom in their crate. The crate has to be the right size though. That is just enough room so they can turn around and lay down comfortable. This method doesn't work at all for Ellie even in a small crate. She eliminates whenever she feels like it.
Lots of people have been successful with this method though.