The quiet ask
The first practical step is to replace the ladder with one instruction that's built to be heard. Everything in this chapter is my own method, and the reasoning behind it is in chapters 3, 4 and 5. Parts of it echo advice on the NHS page on difficult behaviour, which I'll mention where it does.
Go to the child. Not from the kitchen. Not from the doorway. Walk to where they are, get down to their level, and wait until they look at you. If they're on a screen, it's fair to say "Pause that a second" and wait until it's paused. An instruction given to the back of a head isn't an instruction. It's background noise.
Say it once. One thing, in a normal voice, with the words you'd use to another adult. "I need you to lay the table now, please." Not "Can you lay the table?", which is a question and invites a no. Not "How many times have I asked you?", which is a complaint. One clear thing.
Say when. "Now" or "when this episode ends" or "before you go back to that". Children need the edge of the instruction to be visible. The NHS suggests explaining why when it helps, and with older children a short reason is fine. "Tea's in five minutes."
Then wait, and don't repeat. This is the hard part, and it's the whole change. You've said it once. If you say it again, the first time wasn't real, and the ladder has started. Stand there. Count ten in your head. Most children, faced with a parent who's come to them, said one thing, and is now silently waiting, do the thing. It's much harder to ignore a person than a voice.
If they do it, say so. "Thank you. That was quick." The NHS advice is to be specific about what pleased you, and I'd second it. Not because praise is magic. Owen's review found its effects mixed. But because a child who's just done the thing the first time needs to know that the first time is now the arrangement, and a quick, plain thank you is the receipt.
If they don't, follow it through. Chapter 18. Not a second ask. Not a louder one. The thing you'd decided would happen.
Two things about the voice. Keep it low. A low voice carries seriousness better than a loud one, once the loud one has been retired, and it's physically hard to be furious in a whisper. And keep the ask short. The longer the sentence, the more of your annoyance gets into it and the less of the instruction gets through.
This will feel slow at first, because walking to the child takes twenty seconds and calling from the kitchen takes two. The twenty seconds replace four asks and a shout. It's the best exchange in the book.