Agree the deal with the rescue first
Good fostering starts before a kitten crosses your threshold. Sit down with the rescue and settle who supplies food, litter and veterinary care, which vet to use, and what to do at midnight if a kitten goes downhill — young kittens can fade fast, and you want a phone number, not a dilemma. Ask what age or weight triggers adoption, whether you will host adopter visits or the rescue handles them, and what happens if a kitten is returned. Get it in writing, however friendly the arrangement. Also be honest with yourself about the ending: fostering means loving kittens competently and then letting them go, and agreeing that with your household in advance saves tears and last-minute keeps that block your room for the next litter.
Set up one warm, washable room
Choose a small room you can clean properly — a bathroom or spare room with hard flooring is ideal — and kitten-proof it at floor level: block gaps behind appliances, tuck cables away, remove anything chewable or topple-able, and check the door closes securely. Kittens need warmth above all, so provide a box or crate lined with washable blankets and a safely covered heat source for the youngest, arranged so they can crawl away from it if they get hot. Add shallow litter trays they can climb into at the opposite end from food and bedding, a water bowl too heavy to tip, scratching material, and toys that can be washed between litters. Keep the room's door routine strict if you have resident pets, who meet the kittens only if and when the rescue's health guidance allows.
Feeding and watching them grow
Feed exactly what the rescue specifies, little and often — newly weaned kittens eat small meals several times a day, and orphans young enough to need bottle-feeding follow the rescue's schedule around the clock. Weigh small kittens regularly, ideally daily for the fragile ones, and write the numbers down: steady gain is the clearest sign all is well, and a kitten who stalls or loses while littermates grow is your earliest warning to call the rescue's vet. Watch litter trays too, since loose stools dehydrate a kitten quickly, and keep a simple log of appetite, weight and anything odd. That notebook becomes gold later, because it lets you describe each kitten's health and habits truthfully to adopters.
Raising kittens people will want to adopt
Your second job is socialisation, and it is mostly delightful work. Handle each kitten gently every day, touch paws and ears, and let them experience household sounds, different voices and short visits from calm friends so strangers are not a shock later. Play with wand toys, teach them that hands are for stroking rather than wrestling, and watch their personalities separate — the bold explorer, the lap-warmer, the thoughtful watcher. Photograph them in good daylight doing what they actually do, and write honest adoption notes in the rescue's style: a truthful description places a kitten in the right home and prevents the returns that undo everyone's work. If the rescue allows, meet adopters yourself; your lived knowledge of each kitten is the best matching tool there is.
Letting them go well
When adoption day comes, send each kitten out with a familiar-smelling blanket, a small supply of the food their stomach knows, and the log you have kept. Expect a pang, and expect the rescue to fill your room again sooner than you think, which is precisely the point of fostering — your spare room becomes a bridge dozens of kittens cross. KinsLe's Transferrable Profiles complete that handover properly, moving each kitten's feeding history, veterinary records and daily routines to their new owner intact, so the adopter's first week builds on everything you learned rather than starting from a blank page.