It's meant to be the happiest time of the year but Christmas is also when accident and emergency departments are heaving, fire brigades are called out to festive fires and divorce lawyers are gearing up for January – their busiest month. So how can you remain unscathed?

Drink in moderation

It wouldn't be Christmas without warnings not to drink too much. Drinking will relax you, but too much makes you moody and aggressive (because alcohol is a depressant). The hangover you get the next day is officially untreatable (according to an article in the BMJ) – from aspirin and bananas, to Vegemite and water, there is no scientific evidence that anything works. This is also true for complementary therapies such as prickly pear and borage. The one remedy that does work is not drinking too much in the first place. "The drinking is really key to whether you have a happy Christmas," warns Kathryn Hill of the Mental Health Foundation. "You need to pace yourself and drink in moderation."

Accidents due to drink driving also rise over Christmas. The legal limit is 80mg for every 100ml of blood in our bodies – which equates very roughly to one large glass of wine for women and two pints of beer for men. But this would put you at the limit, and some people metabolise alcohol more slowly than others. If you're at a party, the measures you're given will differ to those in a pub. Alcohol increases risk-taking behind the wheel so drinking soft drinks if you're driving is best. Otherwise pre-book a taxi or negotiate who's driving before you start drinking and it's too late to assess how merry you are. Strong coffee or a cold shower will not shift the alcohol through your body faster or make you safe to drive.

Keep the kids safe

Christmas is particularly hazardous for children. "If you've got small children it can be easy to forget all the little things that can accumulate on the floor at Christmas," says Katrina Phillips, chief executive at the Child Accident Prevention Trust. "Plastic toys from crackers and those small silver button batteries are very attractive to small children who can choke on them. Check what's on the floor repeatedly."

The kitchen is more hazardous than ever: "The kind of meal we prepare is more elaborate," says Phillips. "There are more things to get in and out of the oven, there's the rush to boil the water for the gravy and if in the midst of this there are children running through to show the adults their latest toy, this can cause accidents such as scalds, which can be awful."

If you're visiting over Christmas, remember other people's houses may not be child- proofed. "You'll have to be tactful," warns Phillips. "but make sure no one's left their pill bottles on the bedside cabinet where children can reach them and that you move the toilet cleaner out the way."

When you're shopping for toys, make sure they're age appropriate (however advanced your child is) so that a small child won't choke on it. And market stalls may sell cheap toys, but you need to check they are made to safety standards.

Don't fan the fires

The fire brigade is busy at Christmas time – all those candles and wrapping paper. Blow out candles, keep them away from children and check Christmas lights for frayed wires, loose connections or broken sockets. Turn everything off, especially kitchen appliances, and unplug fairy lights at night.

Don't leave food that's cooking unattended in the kitchen and don't cook when you're drunk – both increase the risk of fires.

Stop the stress

Christmas is meant to be the best day of the year. So it's hard not to fall into the trap of setting huge expectations – meaning you'll feel horribly stressed and underwhelmed. Plan ahead – don't leave shopping until the last minute – and get everyone in the family involved in the preparations. Traditionally women bear the brunt of Christmas work but giving everyone a job, from clearing up before the event, to wrapping presents and preparing the vegetables, to laying the table and keeping children entertained, helps share the responsibility.

If you are going to stay with relatives or friends, discuss beforehand who will do and pay for what, as well as how long you'll be there. Every family has their own Christmas traditions (which they'll follow obsessively), so work out the day's timetable before the children rip open their presents. If it's your house then your rules should prevail but if they don't – count to 10 and let it go: don't ruin the day. Do some things together, such as board games or going for a walk. Try hard to be tolerant.

It used to be thought that the pressure, and for some people the loneliness, of Christmas meant a surge in suicide attempts. But studies show that there are fewer suicides than average and fewer hospital admissions for psychiatric problems. An American study of seven years of Christmas mental health problems, carried out by researchers from Duke University, found that the days before Christmas saw falls in the number of severe psychiatric problems but there was a rise in admissions for mental health problems in the weeks afterwards.

More regular amounts of Yuletide stress can be dealt with by yoga, nipping out for a walk, jog or swim or by having a warm bath, and the Mental Health Foundation also has an online stress reduction course (bemindful.co.uk).

Exercise will have the benefit of reducing anxiety and mild depression and boosting self esteem – all of which are valuable at any time of the year.

Don't skimp on sleep (easy to do with parties, drinking and all that excitement) because you'll feel less able to cope with Christmas Day. Be organised: try to avoid wrapping presents after midnight on Christmas Eve.

Don't overspend

Overspending is bad for your bank balance and your mental health. It is a big source of mental distress. A study from Mind, the mental health charity, found half of us overspend at Christmas and one in five will have problems meeting their rent or mortgage payments because of buying presents. So have a budget and stick to it – tell your children they can't have everything they see and watch them grow up to be better people because of it. Studies show that people prefer presents that mean something to them and show the person who bought it knows what they like.

Don't fight with your spouse

Couples often brave it through Christmas only to rush down to the divorce lawyers in January. Spending time together can be helpful if your relationship is struggling – or it can be the death knell. Be considerate and give yourself some time together that isn't shopping, wrapping or cooking.

Enjoy eating

People often worry after the event that they've eaten too many saturated fats and too much sugar. They probably have, but this is Christmas. It's better to go for lower fat, higher protein snacks such as nuts rather than mini mince pies, but studies show most people only put on about 1lb at Christmas. A study published in the New England Journal of Medicine found that one in 10 people put on 5lb over the Christmas period (but, as this research was done in America, it took into account Thanksgiving as well).

Be prepared

Make sure you have enough prescription tablets over Christmas and even if you think you won't be having sex, make sure you have stocked up with contraception.

Think of others and you'll feel better yourself

There's a body of research – and who cares how robust it is – showing that if we do good things for other people, it makes us feel happier. So invite a friend or relative you think might be lonely for a drink, or, if you want to be deliriously happy afterwards, for Christmas lunch. Do some charity work or help out at a Christmas community meal for older people.