We’ve all had that moment at a dinner party where we say or do something we think is totally reasonable, only to realise fellow guests are looking at us with confusion. From turning up at the wrong time to committing a cutlery faux pas, the smallest slip-ups can quietly give the wrong impression.

According to Julius F. Smith, a former royal butler who served Queen Elizabeth II and the host of London’s Regal Afternoon Tea experience, these mistakes are more prevalent than you’d think. Here are the nine things you’re doing at dinner that are making you look unsophisticated and, gasp, common.

Turning up empty-handed

Yes, it almost always entails a last-minute dash to the shops. But according to Smith, it’s still absolutely essential to turn up with a gift, else you’ll immediately make a poor impression.

‘Today, we seem to have lost the art of bringing a gift if we are invited to someone’s home,’ he says, ‘and often we turn up empty-handed. However, in most societies around the world it would be unthinkable to not bring anything. Even a small gesture given with thought can be wonderful.’

That said, there’s an art to picking the ‘right’ gift. ‘Gifts can be a potential minefield, especially if you arrive with something that is completely not to the taste of your host,’ Smith explains. ‘The two well-worn standards are a bottle of wine or a small bouquet of flowers.’ And be prepared to splash out. ‘You cannot bring a cheap bottle of plonk,’ he warns, ‘especially if the host is planning on serving something special for the evening.’

Want to go one step further? Book a cleverly timed delivery. One of Smith’s favourite flourishes is to ‘send the flowers to the house earlier in the afternoon, before you are due to attend. This is very good manners – and make sure to enclose a card so your host knows exactly which guest had this marvellous idea.’

Asking for the WiFi code

We all know it’s bad manners to use your phone at the table – and Smith says however sneaky you think you’re being, your host is well aware if you’re stealing glances.

‘Of course, everyone is going to say you should not use your phone whilst having dinner as a guest,’ he says. ‘However, saying and doing seem to be two different things to most people. How many people have not put the phone on their laps under the napkin and taken a crafty peek?’

And then there’s a pet peeve of Smith’s that instantly lowers the tone. ‘Another no-no is to ask for the WiFi,’ he reveals. ‘A new fad that’s transferred from restaurants seems to be guests photographing their dinner party food and then, heaven forbid, posting online.’ Gauche.

Drinking too much

You’re meant to relax and indulge at dinner parties, and if you’re a drinker, that’ll often mean a few more glasses than usual. But as Smith reminds us: ‘No one wants to be the person remembered as the drunk at the dinner table.’

It’s easy to get carried away when drinks are flowing freely, which is why a bit of forward planning helps. ‘If you know beforehand that copious amounts of wine will be offered, try not to drink earlier in the day, and try to monitor your refills.’

Because, as we all know, once things start to unravel, they get ugly very quickly. ‘A drunk can turn into a bore who finds their own jokes too funny and be a little flirtatious,’ Smith warns, ‘who then struggles to remember the morning after what had happened the night before.’ And flirting with your host’s husband is a surefire way to ensure you’re never invited back.

Sitting down too early

Yes, you might be hungry. But your host announcing it’s time to sit is ‘not an excuse to rush to the table like Usain Bolt,’ Smith says.

Instead, follow the flow of the evening. ‘You follow the other guests into the dining room in an orderly manner and once at the table, you wait to be told where you are to be seated. If you have a lady next to you, help her by pulling out the chair and allow her to sit first.’

And once the food is served, don’t immediately tuck in as though you’re coming off a hunger strike. ‘When the food arrives, you wait until other people start eating,’ Smith says. ‘The only thing worse is a guest who does not keep up with other diners and fails to finish eating with everyone else. Some people have no sense of awareness.’

Arriving too early

Most of us understand it’s not okay turning up late. ‘We all have friends and acquaintances who are always running behind,’ Smith says. ‘But I can assure you that there is no such thing as “fashionably late” – you are either on time, or not.’

But many don’t realise it’s just as problematic to turn up earlier than stated on an invite. ‘If you have been invited for dinner between 7:30pm and 8pm,’ Smith says, ‘the perfect time to arrive is 7:40pm. We do not arrive at 7:30pm on the dot, and heaven forbid arriving before the allotted time, as our hosts may not be ready for our arrival.’

Snooping around the house

‘We are all curious about other people's houses,’ Smith admits, ‘and, when invited over for dinner, it may seem a perfect time to have a nosey around the house whilst the host is in the kitchen.’

But even if the temptation is there, ‘the simple answer is don’t. You patiently wait in the reception room you have been shown into. If, for example, it’s a newly bought home, in most cases you may well be given the grand tour anyway.’

Holding cutlery incorrectly

In the comfort of your own home, you’re more than welcome to shovel your food in with your fork in your right hand. But according to Smith, ‘standards seem to be getting poorer and poorer’ at dinner parties – and it’s one of the quickest ways to make yourself look unsophisticated.

And other mistakes are impossible to miss. ‘Some people seem to cut a piece of meat with their knife like one of the murderers on the Orient Express. We also do not tuck our napkin into the top of our shirts – it is not a bib.’

Forgetting to mention allergies

While it’s difficult having allergies, Smith says that someone’s house is ‘not a restaurant, and as such, they may forget or simply not ask whether you have any dietary requirements. It’s good form if they do ask you, but if they don’t, it is still your responsibility to let them know so they can make the necessary arrangements.’

And sorry – if you simply ‘don't like’ an ingredient, you’ve got to suck it up. ‘Don’t make it obvious and turn your nose up,’ Smith says. ‘Think of England and do your best to eat what you can.’

Not knowing when to leave

Imagine it’s the end of the night, says Smith. ‘Everyone had a wonderful evening, the food was fabulous, the cocktails and wine particularly good, and everyone was on fine form. It is now time for the guests to leave.’

But how do you know when to make your exit? ‘Usually,’ Smith advises, ‘after one of the guests has made the first move to vacate, this should prompt the other invitees to think about making tracks.’

‘This is not an invitation to think about hunkering down and settling in for the rest of the night. Everyone has a home to go to – so make a move to yours.’