STAND STRAIGHT, clasp the hands at the side, bend from the waist and tilt the head forward. Keep the eyes cast down and watch for the reaction of your guest.
The precise etiquette of Japanese bowing, particularly calibrating the angle and depth required to express the proper respect to the receiver, has long flummoxed foreigners - just ask US president Barack Obama.
In his weekend meeting with Japanese emperor Akihito, Mr Obama took no chances, bending his lanky frame by the full 45 degrees for maximum deferential effect. But the sight of the 6ft 1in leader of the free world kowtowing to the diminutive monarch - eight inches shorter - has outraged US conservatives, who say it has belittled Washington's status abroad.
"Groveller in Chief" and "O-Bow-Ma" are two of the more printable names that have zinged around the pundit-sphere since the now infamous meeting of hereditary and elected power.
The Washington Postcalled it a "shocking display of fealty to a foreign potentate", while commentators on Fox News, CNN and other outlets lined up to call it undignified, unctuous and even treasonous. "I'll bet if you look at pictures of world leaders over 20 years meeting the emperor in Japan, they don't bow," conservative commentator William Kristol told Fox News.
A YouTube clip comparing Mr Obama's horizontal curtsy with stiff-backed handshakes by former US vice-president Dick Cheney and other imperial guests appears to prove the point, and is getting tens of thousands of hits a day.
The president's performance has gone down well in Japan, despite opposition to Washington's plans for a new military base there. Although little noticed at first, his bow has become a media debating point since the US controversy erupted, with most people deeming it appropriate.
"It is unusual to see an American leader show so much respect for a foreign culture," said one caller to a show yesterday.
"People here like Mr Obama for that."
But elsewhere the display of diplomatic courtesy is increasingly being seen as a symbolic moment, at a time when US power and influence abroad appear to be waning.
The man who calls himself "the first Pacific president" is on a mission in Asia to shore up that power, and strengthen strained ties with Japan and China - the US's largest creditors.
Meetings with emperor Akihito, whose father, Hirohito, led Japan into war with the US in 1941, are watched particularly closely in the US.
In 1994, then-president Bill Clinton was dubbed "obsequious" by the New York Timeswhen he pitched forward at an awkward half-mast.
In the most famous photo of all, Japan's wartime conqueror, Gen Douglas MacArthur, hands on hips, loomed over a stiff and formal Hirohito when the two enemies met for the first time in 1945.
Mr Obama's aides are trying to defuse the row before he returns to the US at the end of the week. US state department spokesman Ian Kelly called it merely "a sign of respect to the emperor".
But the image is likely to live on among the president's critics long after he is back in the White House.