By definition, your bedroom should be the most peaceful place in the house, with bed the apex of that harmony. You should no more use your bed as a battleground than you should think of taking a shower over your PS4. Avoid conflict at any cost, even if that means a moratorium on all conversations that aren’t about sex or bitching about other people.

Humans being what they are, however, means we are capable of arguing endlessly about even the core traits of the place where we intend never to argue. Last week, a Twitter user sparked heated debate when he innocently mentioned that he and his partner alternated sides of the bed: “Some nights I like to sleep by the window, some nights the door. It’s not really that unusual, is it?” Let’s establish some ground rules, shall we?

Should you take your phone or tablet to bed with you?

No way. Not unless you want to risk the accidental checking of work email, the whirring thoughts, the cascade of emotional reactions that social media provokes. “I would very much like people not to be using their mobile phones as their alarm clocks,” says Dr Guy Meadows, the founder of The Sleep School and the author of The Sleep Book. “So that they are never looking at their phones in the middle of the night. Your mobile device contains your entire daytime waking life. It’s not designed to be next to you in the bedroom, and the rationale for that is a simple light perspective. We have these incredibly light-sensitive cells in our eyes which inhibit the release of melatonin and activate the release of cortisol, basically pushing sleep further away.”

I left my phone downstairs by accident once, and found it conducive to good wifeliness, in that I wasn’t constantly chuckling at other people’s jokes and forcing my partner to watch videos of the time a racoon pretended to be a cat.

What is it acceptable to eat in bed?

‘Avoid eating food very late at night.’ Photograph: South_agency/Getty Images

It’s more “when”; that determines the “what”. Dr Paul Kelley, an Oxford academic and the author of Body Clocks, can’t see anything wrong in principle with eating in bed (“Maybe crumbs?”) but reminds us “not to eat food very late at night, because you are still digesting when you should be sleeping. But breakfast in the morning is nice.” Not sausage casseroles, in other words. Yes to croissants, although this does mean more crumbs.

Should you have separate duvets?

If you can share nicely, like decent people, then of course not, but if you can’t – perhaps one of you is like a furnace and the other has a cold, cold heart, which emanates to their extremities – then sure. Kelley has one of those beds with two separate mattresses on the same base, to accommodate different heights, different musculoskeletal ailments, all the small disparities that might exist or, over time, accrue between two people but needn’t bring any build-up of ill will at all. Unlike …

Is it acceptable to sleep somewhere else if your partner is asleep and you are staring at the ceiling?

The curse of disparate sleeping patterns will be familiar to many couples. It cuts so much deeper than other marital classics such as one eating no fat and the other eating no lean (this apparently works out quite well). The couples therapist Pauline Rennie-Peyton says: “No one’s going to find the perfect sleeping partner.” Since we all know that, we tend to make do. Rennie-Peyton continues: “It usually comes up when people are going through conflict in other areas of their life.” This is the worst possible time for it to come up, since resolving conflict ultimately requires empathy, and that comes from the bit of the brain that a lack of sleep closes down first. And the underlying impulses are quite unreasonable. “If you’ve got one person who sleeps better than the other, the other person is often jealous of them.” This is as petty and fruitless as envying someone’s red hair. Separate beds, however, are not to be toyed with. “Then does it get to separate rooms?” Rennie-Peyton asks.

Kelley has an interesting alternative perspective. “Humans are distinct from other primates, in that they have the shortest period of sleep and they sleep on the ground.” This last bit leaves them unusually vulnerable to predators. “So when there’s someone asleep, there’s someone else awake.” Wait. You mean we have evolved to choose a mate who is likely to be awake while we are asleep? Not quite. But we are not necessarily coded to co-sleep.

Solomon-like, I adjudicate that the effects of one partner sleeping badly are so profound for a relationship that they offset the affection of sharing a bed. Sloping off to the sofa is a reasonable compromise.

Who gets up when the baby cries?

Assuming there is no breastfeeding involved, you can do French rugby rules (whoever didn’t do it last time) or a complex negotiation based on who is most tired at the end of the day (a war of attrition never truly resolved – one person will just give up). But it is easier to accept that it will always be the lighter sleeper and let guilt bring a rebalancing in the morning. The good thing about babies is that they bring no shortage of things someone doesn’t want to do.

How do you minimise the disturbance from your alarm?

Photograph: Image Source/Getty Images/Image Source

It needs to make some disturbance, doofus, or it won’t wake you up. The better question is: how do you maximise disturbance? When I turned 30, my mother got me a bespoke alarm designed for deaf people and it was tremendous and terrifying, noise and light and mad vibration, like being arrested and hearing a four-minute warning at the same time. We called it alarmageddon. That was about as stressful as any alarm can be, but it wasn’t as stressful as the time I slept through an alarm and was three hours late to interview the boyband Blue.

Who gets to decide when the light is turned off?

Guys, this is really basic: you make these decisions with sensitivity and mutual respect, or failing that, the laziest person, who is also the deeper sleeper, makes the decision unilaterally by closing their eyes, then the other person turns the light off. But one thing is important: whoever decides has to be consistent. “The single biggest health tip that I’d give anyone is to keep yourself on time,” Meadows says. If you abuse your body clock with lie-ins, shift work, late nights, you risk “social jet lag”, which is exactly like regular jet lag: headaches, poor digestion, lack of focus.

What is the best way to deal with your partner’s snoring?

Try to avoid blaming your partner. Photograph: Flashpop/Getty Images

Regular snoring can usually be allayed by diplomatic shoving that doesn’t even wake them up. Snoring related to a cold you just have to be empathetic about, since one day you, too, will have a cold. “If someone says to you: ‘When you drink red wine, you snore profusely,’ then they are giving you some kind of choice,” Rennie-Peyton says. “There’s all this blame culture, instead of: ‘Let’s see if we can sort something out.’ Kindness comes into everything, including sleeping.”

One time, my Mr and I had so much mutual kindness that, while I was out on the razzle, he thought he would forestall me feeling guilty about snoring by sleeping in a top bunk that some child had vacated – only I had exactly the same thought when I got back and crept into the bottom bunk, then we were surprised to wake up stacked vertically like sailors.

Who makes the bed?

This is easy: you make it together, as that is quick and has a Little Women kind of wholesomeness. Obviously, you will never feel like doing it at the same time, but now you will feel equally responsible for this shortcoming, so you will get used to your quagmire bed that only gets changed once a year on Valentine’s Day with a rueful acceptance of human frailty, rather than a boiling reservoir of resentment.

Welcome in bed? Photograph: gollykim/Getty Images/iStockphoto

Should you let the dog join you?

Tragically, whoever is most sensitive to the dog’s shenanigans gets to decide whether the dog is there or not, which almost always means not. On the plus side, when that person is away on business, the dog is allowed in the bed. Then it’s like having an affair. With your pet.

So, is it acceptable to swap sides?

No, of course not. What are you, a savage?