Affiliate disclosure: some links below are affiliate links. If you buy through them I may earn a commission, at no extra cost to you. I only link to things I would recommend without one. Full disclosure.

Bringing home a new cat or kitten

The most useful thing you can do in week one is give the cat less space, not more. A whole flat is overwhelming; one room is manageable.

What to have ready before the cat arrives

Litter tray — open, low-sided for a kitten, with unscented clumping litter
Two shallow bowls, food and water, away from the tray
A carrier, left out with the door open so it stops being "the vet box"
A hiding place — a cardboard box on its side is better than anything you can buy
Something high — even a cleared chair or shelf
A scratching post, tall and stable
One wand toy — not a bag of toys

The one-room start

Days 1–3. One quiet room with everything above. Open the carrier and walk away — do not tip the cat out. Sit in the room reading, ignoring the cat, so you become background rather than a threat.
Days 3–5. The cat starts exploring when you are there. Now play. Let it approach you; do not reach for it.
Days 5–7. Open the door and let it come out in its own time. Leave the safe room set up exactly as it is — it needs a retreat for weeks.
Week 2 onward. Gradually add the rest of the flat. Keep the litter tray in the original spot for at least a month before moving it, a few centimetres at a time.

If there is already a cat in the house, this schedule changes — see two or more cats, which takes two to four weeks instead of one.

Hiding is normal

A new cat that spends three days under the bed is behaving correctly. As long as it is eating, drinking and using the tray overnight, leave it alone. Dragging a frightened cat out sets the relationship back by weeks. What you are waiting for is the cat to come to you — and the fastest way to make that happen is to stop trying.

Stopping door dashing before it starts

Door dashing is dangerous in a block of flats — corridors, lifts, stairwells — and it is far easier to prevent than to cure, because every successful escape reinforces it.

Make the door boring. Never feed, greet or play with the cat by the front door. If the door is where good things happen, the cat will wait there.
Build an airlock. A pressure-mounted pet gate across the hall, or simply always closing an inner door first, means a dash gets one room, not the building.
Teach a station. A mat or stool a few metres from the door where a treat appears every time the door opens. Most cats will run to the mat when they hear keys within a couple of weeks.
Come in sideways, bags first, low and slow. Coming in fast with the door wide is how it happens.
Microchip, and register it with your current address and phone number. An escaped indoor cat usually hides nearby rather than travelling; a chip is what gets it back.

Windows and balconies If you are above ground level, screen the windows and never leave a balcony door open unsupervised. Cats misjudge height and ledges far more often than their reputation suggests.

Covers: bringing home a kitten checklist, cat door dashing prevention