Write the routine as times, not descriptions
Consistency starts with a routine a stranger can actually follow: feed at seven and six, this measured amount, in this bowl, with fresh water then; play before the evening meal; lights low after the last check. Vague notes like 'she likes her dinner early' produce a different routine in every pair of hands. Ask the cattery honestly which parts they can match exactly, which they can match approximately, and which they cannot, because a good cattery will tell you their fixed feeding rounds upfront, and knowing the differences lets you shift her home times gradually toward theirs in the week before she goes.
Send the same food, litter and smells
Feed her own food, portioned and labelled, rather than accepting the cattery's house diet, because a sudden food change plus a strange place is the classic recipe for a refused bowl and an upset stomach. Send the litter type she uses at home if the cattery allows it, and her own unwashed blanket and a worn item of your clothing for the sleeping shelf. Routine is partly sensory: the same tastes, tray feel and sleeping smells tell her the important parts of life have not changed, even though the view from her unit definitely has since yesterday.
Keep the rituals, not just the schedule
Every cat has small ceremonies that anchor the day: the greeting at the door, the treat after grooming, the specific game that means evening. Tell the cattery which of hers matter and which they can realistically keep, such as a few minutes of wand play or simply sitting quietly by her unit at the same time each day. Staff who understand that the shy cat needs to be talked to before a hand appears, or that your cat expects food before affection, can reproduce the feel of her routine even inside their own timetable and building rules.
Bridge the return as carefully as the departure
Consistency runs both ways, so when she comes home, step straight back into her original routine rather than inventing a spoiling regime of extra meals and constant carrying, tempting as that is after a separation. If the cattery shifted her feeding times, walk them back over a few days. Ask for their notes on how she ate, slept and behaved, because a cat who ate poorly away may need watching at home, and a cat who loved a particular toy or food puzzle there has given you useful information about her preferences at home too.
Make the routine portable on paper
The routine only transfers if it leaves your head in a form carers can use under pressure, at feeding round speed, without texting you questions across time zones. One clear page, plus her vet and emergency details, beats a long message thread nobody scrolls through mid-round. A cattery that keeps a written daily log of appetite and litter use is gold here, because you can compare it directly with her home pattern. Handing that routine over through KinsLe Care Pass gives the cattery team clear temporary access to her feeding times, rituals and key details, so home and boarding run on the same page.