[Soundy]

The idea with crate training, once you have the dog recognizing that as her "den" and her safe place, is to lock her in whenever you're not watching her... then when you do let her out, take her STRAIGHT outside. If she doesn't do her business, put her right back in the crate and lock her in again.

Dogs by nature will not want to soil their beds, so if she's in there, she'll want to hold it in... thus you simply don't give her the opportunity to mess indoors, but make it so the first opportunity she has to do it, is outdoors.

And as noted, heap the praise on when she does go outside.