Hi
Brumation does sometimes start on its own. Stop feeding the lizards completely, making sure there are no "hidden" crickets, mealworms or superworms in their enclosure. After five days, turn off their lights, and wait an additional 48 hours.
Then, you will need to place them in actual brumation. For posts on how to brumate, do a search on brumation in the forum and you'll probably come up with past posts that offer different suggestions and schemes to provide the optimum brumation conditions and length.
If there are still questions that you cannot find answers for, post again, and we'll try to assist.
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1.2 Collared Lizards
1.0 African House Snake
1.0 Red Sided Garter Snake
1.5 Turkish Angora (show) cats
Antioch Turkish Angoras
Kitnhevn Rescue