You see these yellow cross-hatched boxes found on most London Underground platforms?

They are there to ease congestion in some of London’s busiest underground stations. They are often situated at entrances/exits of the platform so that instead of waiting for the train at the entrance/exit people have to move along the platform. Pretty good right? Only problem is not everyone pays attention to it. Please do not stand in this area, looking at maps or your phone with huge bags or if you’re in a group. This causes so much irritation.

Another thing that really bothers people (especially me) is when exiting a station and you haven’t yet gotten your Oyster or contactless payment card ready to tap out even though you are getting pretty close to the ticket barriers. This then results in you standing in front of the barriers helplessly looking for your Oyster card, with a queue of annoyed commuters behind you. Please get your card ready in advance!

With regards to shopping and customer service, remember to be polite when speaking to the cashier/assistant. Saying “please”, “thank you” and “sorry” is part of the customary code of politeness in London. Not using these words will most likely result in strange faces and possibly getting poorer service. Useful tip: don’t even think about jumping a queue.

Generally speaking, Londoners are quite tolerant about the mistakes visitors make here and won’t confront you about it but avoiding them does go a long way!

Image Source: Google Images

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Phil Gyford, who also lives in London adds

Not a faux pas, but a little error that many Americans make is to omit the "Street" or "Road" etc from names. They might say they went to a shop on "Goldhawk" when they mean "Goldhawk Road". That's fine when your city is full of uniquely-named "1st St", "Avenue A", etc, but doesn't work in London. It sounds very strange to British ears and can be confusing because no one knows exactly where you mean. You say "I'm staying on Pembridge" and you could mean Pembridge Villas, Pembridge Road, Pembridge Gardens, Pembridge Place, Pembridge Crescent, etc.

Sean Dillon, Advertising Operations & Technology says

When ordering drinks in a pub:

• Decide what you're going to drink BEFORE the bar-person gets to serve you. Likewise, if you must order food then make sure you know what you want before approaching the bar.
• If someone else is at the bar before you and the bar-person attempts to serve you first indicate that they the other person was before you. You will get served next. The biggest social faux pas is to jump a queue at the bar.
• Order the Guinness first...
• Remember it does not take 5 people to stand at the bar waiting for their drinks, move out of the way to allow others to get to the bar. Send the others away to find somewhere to sit/stand.
• You can use your credit/debit card but there's usually a minimum fee (usually £10).
• Whilst some pubs might serve them, beer rarely comes in pitchers.

Dermot Hunt, who was Born and bred in Proper London. (Not that nasty Sarrrf nonsense). makes the following comments

Making insufferably tedious and inaccurate generalisations about Londoners. Of course, making insufferably tedious and inaccurate generalisations about any group of people is a bad idea, and the same obviously applies in London. With regards to tube etiquette, try and bear in mind that the London Underground is not a social networking site. It is a functional transport system full of busy people who are trying to get to their destinations as quickly as possible, not a place to try and make new friends. People do not want to stop and talk to you on the Tube, and they also do not want to have to ask you to move out of their way. As such, you should observe one very basic and obvious rule - do not obstruct passageways. This means that you do not stand on the left hand side of the escalator (a crime which should be punishable by summary execution, frankly). Also, don't hang about in platform exits looking at maps. (There are maps available everywhere, and if you don't have your own, you'll find plenty more on the platforms). Finally, allow people to get off the train before you try and get on. IN BRIEF - be considerate to your fellow passengers. Not asking a lot, is it?

Graham Beale, lived in London adds

Londoners are on the face of it, a very tolerant species. The problem is that they are unlikely to tell you directly if you have over stepped the mark. If they do tell you, they have probably been seething for sometime and you are about to witness the dark side of our capital city. Most of the cultural faux pas are around the use of public transport - after all everyone uses it and nobody enjoys it. So, here are the things you should never do:

• Play loud music on your mobile
• Play loud music which you can overhear through earphones
• Eat smelly food
• March on the tube/train/bus without first letting folk off
• Talk loudly on your mobile phone
• Read a huge newspaper and elbow folk either side of you
• Stand on the left of the escalator
• Stand right in the 'flow' of the pedestrians with a suitcase looking bewildered
• Drink alcohol on the tube (they can fine you)
• Verbally abuse the driver
• Touching other peoples hands when trying to hold on during transport
• Fumbling for your travel card before you enter the aisle
• Waiting for assistance at the aisle when folks are trying to get by you
• Have body odour
• Stare
• Shout at friends the other side of the carriage

I'll add more if I think of them...

Maxine Welford, who is Telemarketing for Accountants and Professionals, Social Telemarketing, and Marketing Support adds

• Either walk on the escalator or move to the right out of the way.
• Have tickets ready and don't put them in the wrong way round
• Jumping queues for cabs
• Nicking other people's cabs
• Calling everything "quaint"
• Assuming every Londoner uses or understands cockney rhyming slang
• Mispronounce "Pall Mall" it's not a shopping mall
• Flash lots of cash around unnecessarily
• Walking too slowly in busy areas
• Not standing on tube in a robust enough manner with feet slightly apart for balance and bumping into people who are trying to avoid being bumped in to
• Make creepy comments when pressed up next to females on the tube about it being cozy, or apologising frequently, or if taller avoid looking towards cleavage area at all costs
• Bad breath on busy tubes or body odour

Alx Klive, who Lived both sides of the pond for many years, expert in locating Marmite adds

Wow there’s a lot of talk about commuting here… All valid I suppose, but I'm going to try to balance it out. (Tourists should probably avoid traveling during commute times anyway). In general, Londoners, like all Brits, are exceedingly polite, and are generally brought up not to make an exhibition of ourselves. We therefore look unfavourably on people being impolite, brash or selfish. We’re tainted by our own views of people from certain countries, and this has to be considered as well. For example, Americans sadly have a poor reputation in the brash department in London, so talking loudly in an American accent in public, is probably going to be an American's biggest faux pas of all (sad, but probably true...) We generally like people not to fit their stereotypes, so on a positive front, being the opposite of what Londoners expect, will undoubtedly get you far… Here’s my 25 practical tips, in approximate order of ‘crime’…

1. Avoid talking loudly or obnoxiously in an American accent in public (say you are Canadian if so... If you are Canadian, say you are American).
2. Do say please, thank you and cheers (we find it curiously endearing).
3. Don't say you read the Daily Mail, or ever be seen reading one.
4. Do buy a round of drinks when it’s your turn, ideally before.
5. Don't jump the queue (cut in line = bad).
6. Don't create a fuss in public as a foreigner, it takes a lifetime to learn simply when you can do this as a Brit.
7. Don't be a drama queen at all. If you’ve lost your phone, luggage, passport, ecstasy pills… deal with it, don’t lean too much on your recently formed acquaintances and hosts.
8. Do generally turn down offers of assistance (which may not be sincere, particularly if you are being a drama queen - see above).
9. Don't take things that have been said sarcastically as being serious (not a big faux pas if you do - we are quite used to people doing this).
10. Don't take friendly banter and put downs as being serious, or be offended by it. This is just how we talk to each other.
11. Don't root for another team too loudly (if watching football and surrounded by opposing fans).
12. Do buy your hosts a gift, or take them out to dinner (pretty universal).
13. Don't say a prayer before dinner - unless you are on a mission.
14. Don't look at your phone constantly in social situations (unless you’re under 25).
15. Do make your own way from the airport (if you are over 25).
16. Do drive on the left if you rent a car, and be accommodating to other drivers in general. Let them pass, let them in, and leave lots more space between you and the car in front compared to other countries. Blame the Highway Code for this (you'll have to ask a Brit).
17. Do be a gentleman and pay for everything if on a date (edit: unless you are a millennial? - see comments below).
18. Don't hit on your friend’s partner (pretty universal).
19. Don't ask the DJ to play a tune (unless it’s a wedding, and then only if you must).
20. Don't tell the guest list person or bouncer a story - they’ve heard it all before.
21. Avoid discussions on politics, religion, war, and anything too serious in social situations, unless someone brings it up first. When Londoners relax we tend to joke around.
22. Do start discussions about property, sport and television - our three favourite subjects.
23. Do be aware that some pubs are not always welcoming to non-locals, particularly in working class neighbourhoods. Do evaluate a pub and its clientele before striding in with your family from the airport.
24. Do be aware you will be judged on which part of town you are staying in. Most areas of London have strong stereotypes attached.
25. Do have fun, and get drunk (but find your own way home).

Ernest W. Adams, who lives in The United Kingdom adds

Numerous people have mentioned standing on the left on an escalator as bad form, but no one has mentioned something even worse: coming to the end of an escalator or a moving walkway, AKA travelator, stepping off, and stopping dead to decide what to do next. Other people are coming up behind you and have no way to stop and wait while you clue in. Get out of the way if you don't want to be slammed into. Stepping out of a door onto the street and then standing around gawping and blocking the door is another major irritant. Even some of the British do this one. For some reason it's often young women. Finally, talking loudly, at any time, anywhere, for any reason is deeply gauche. Some men have booming voices and need to be told. Don't do it in the Tube, aboard buses or trains, in restaurants, or in a pub. If you have just gashed your femoral artery in a pub brawl and require medical help instantly or you'll bleed to death, say, "Would you ring for an ambulance, please?" to the bystanders. Shouting at them hysterically will only tempt them to let you die. Britain underwent months of bombing by the Luftwaffe and nobody ever raised their voice or lost their temper, so belt up.