In the winter months it's critical to make sure you are misting your Crested Geckos adequately. As the temperatures drop outside, we crank up our own heat indoors which can dry out our Crested Geckos' enclosures.
Misting your adult and subadult Crested Geckos extra heavily in the evening during winter months should be more than adequate to maintain proper humidity and water droplets for drinking. Juvenile and hatchling Crested Geckos are more concerning though as they can dehydrate quicker.
For my juvenile and hatchling Crested Geckos here at NiceRhac.com I house my juveniles and hatchlings in larger tubs in small groups. I know some Crested Gecko breeders prefer to house geckos individually but for me, it is much more convenient and easier to ensure fewer larger cages are getting properly misted versus hundreds of smaller tubs. In the spring I move juvenile and hatchling Crested Geckos to individual housing. I also like to add moistened sphagnum moss in a small deli cup to ensure humidity remains adequate inside my juvenile and hatchling Crested Gecko tubs.