Tap in, tap out

Don't queue for paper tickets. A contactless card or your phone works as an Oyster on every Tube, bus, Overground and most trains in the city, and the daily fare is capped automatically so you never overpay. Stand on the right of the escalator; walk on the left, or a Londoner will tell you about it.

Four seasons before lunch

British weather is not a national myth. It genuinely turns from sun to cloudburst and back within an hour, in any month. Carry a small umbrella and a layer even on a clear June morning, and don't cancel the open-top bus over a grey forecast. The rain usually passes; the locals just carry on.

The pub is the village hall

You order and pay at the bar, not at the table, no one will come to take your order. And you don't tip the bartender. Sunday lunch is the roast, booked out by one o'clock in the good ones. The pub is where Britain actually socialises; treat it as the living room, not just a bar.