Start with health, not the calendar
Hibernation is a fast, and only a tortoise with the reserves for it should undertake one. Before any wind-down begins, he should have been eating eagerly, active in warm weather, passing normal droppings, and clear in the eyes and nose with no wheeze, discharge, or recent illness. Weigh him and note the weight against his length so you have an objective starting point rather than a feeling. A tortoise who has had a poor summer, is new to you with an unknown history, is very young, or has been treated for illness is a candidate for staying awake this winter under lights, or at minimum for a vet's opinion first. Species matters too — this wind-down applies to the commonly kept temperate species that naturally hibernate, not to tropical tortoises who must never be chilled.
The wind-down: food, baths and light in step
Over roughly three to four weeks, mirror what autumn does outdoors. Shorten his access to heat and light gradually, and reduce food over the first part of the wind-down, then stop feeding altogether for the final stretch while water stays available. The point of the food-free period is that he enters hibernation with an empty gut — undigested food sitting in a cold tortoise is a genuine danger. Warm baths several times a week do double duty through this phase: they keep him hydrated, which matters enormously for surviving the sleep, and they encourage him to pass the last of his gut contents. You should see droppings tail off to nothing as the wind-down completes.
Weigh, record, then choose the setup
Weigh him at the start, through the wind-down, and on the day he goes down; the record tells you his trend and becomes your baseline for the in-hibernation checks. Then settle him into the prepared fridge or insulated box at a steady temperature in the low-to-mid forties Fahrenheit, in dry bedding he can bury into slightly. Label the setup with his details and the date, because a sleeping tortoise in an unmarked box is an accident waiting for a helpful relative. Juveniles and small tortoises hibernate for shorter periods than large adults, and a first hibernation should be kept short and closely monitored rather than ambitious.
Monitoring through the sleep, and waking well
Preparation includes planning the supervision: weigh him at intervals through hibernation — a healthy tortoise loses very little weight across the whole sleep — and check the temperature regularly. A tortoise who loses weight steadily, urinates in the hibernation box, or stirs persistently in warm spells should be woken rather than left: bring him up to room temperature, then under heat, offer a warm bath before food, and expect drinking to come before appetite. If anything about his condition worries you at any stage — before, during, or after — a vet check is the right call rather than perseverance. The thread through all of it is record-keeping, and that is where the KinsLe Pet Passport earns its place: his weights, health notes, and hibernation dates live together in one packet, so next autumn's wind-down is planned from his actual history.