It’s the season of coughs, sneezes, sniffing and the inevitable runny nose – and most of us know what it’s like to suffer the embarrassment of needing to blow our nose at a less-than-ideal time (in a confined environment, for instance, at an important business meeting or, worse, around food).

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So, is there a right and a wrong way to blow your nose?

“Absolutely,” says etiquette consultant William Hanson, author of The Bluffer’s Guide To Etiquette. “You don’t want to expel any bodily fluids directly in front of someone.”

Here’s Hanson’s guide to blowing your nose like a pro.

The right way

If you need to blow your nose, you should turn away (from everybody else), face downwards, and cover your nose with some sort of handkerchief or tissue.

Keep away from food if you need to blow your nose, and if you really have to do it, wash your hands or use anti-bacterial gel to avoid germs spreading. Always keep tissues and gel handy, in a pocket or somewhere where they are quickly accessible.

The wrong way

“The worst way would be to sneeze into someone’s face and then not even say, ‘Excuse me’, and think they won’t notice. And it has happened to me before, especially when you end up with moisture on your face,” says Hanson.
Never wipe your nose with your sleeve, or look at the contents of the used tissue or handkerchief in front of others.

Hanky or tissue?

“It really is the sign of a gentleman or a lady to carry around a nice white cotton handkerchief. Hygienists generally freak at the concept of a handkerchief, but I would normally only use a handkerchief once, not keep using it,” says Hanson. “Obviously, if I’ve got a streaming cold then I would use tissues, as they are more practical. But cotton handkerchiefs are much softer on the nose than a coarser tissue.”

[Read more: Cough etiquette: 7 ways to make sure yours doesn’t annoy people]

At a dinner party

Sometimes, cancelling really might be the politest option, says Hanson.
“If you have a terrible cold then you’ll have to cancel, because no host wants any guests with any ailments bringing down the tone of the party. But if you do suddenly have a sneezing fit in the middle of the main course, just politely excuse yourself from the table, go to the lavatory and get the blowing over and done with, before returning to the table with the minimum of fuss,” he says.

In confined areas on public transport, like the Tube
“Turn away from people, drop your head and sneeze downwards, rather than to the side. The main rule is to turn away. Carry anti-bacterial gel with you, so that If you sneeze involuntarily and you haven’t had time to get your handkerchief or tissues out and you sneeze into your hand, you can use the gel on your hand before re-attaching your hand to the rail.”

In the boardroom

“If it’s a quick blow of the nose and you don’t have a streaming cold, just turn away, blow your nose, turn back and carry on. Nobody is going to have an issue with that. If you have a terrible cold and there’s a lot of stuff up there that no-one wants to hear come out, excuse yourself, apologise, and explain that you’re just going to step outside. You don’t need to tell people what you’re going to do, just step outside, do it and come back in. People will appreciate the fact that you’ve considered others.”

At the theatre or in a church

“Ideally, wait until you can get away with blowing your nose without people hearing it. Wait for a noisy bit or a song in a play when people aren’t going to hear you, or when the organ starts up in a church. But if you have a sneezing fit you’ll need to get up from your pew or your row and go and blow your nose in the foyer.”

Is it OK to sniff to avoid having to blow?

“One sniff is fine, two sniffs is unfortunate. You then need to do something about it. No one is going to be attracted - romantically, professionally or socially - to a sniffer.”

The key is to be prepared

“You may want to take numerous handkerchiefs out with you or several packets of tissues along with any medication to help ease your cold. But it’s incorrect to take medication in front of other people, whether it’s a pill or nasal spray. Do that away from people. If you are at your desk or with clients or friends, take your medication in the bathroom.”

But, when in Japan…

Hanson advises that etiquette rules can vary in different countries. “Blowing your nose in front of anyone, whether they are your partner, friend or your client, is the worst thing you can do culturally in Japan. They see the expelling of bodily fluids in front of people as grim. If you’ve had a cold and you keep sniffing in front of someone, they would see that as much more polite than if you blew your nose.”