But of all the advice English took, it was the longstanding adage "smile and the world smiles with you" that appears to have stuck.
English has barely stopped smiling since he became Prime Minister.
On his first overseas trip, English gripped and grinned his way around Europe with such commitment he will return to New Zealand needing physio on his cheeks.
He arrived in Europe smiling, despite more than 30 hours of travel and arriving at Brussels by train to the grimy red light district rather than to a red carpet welcome at the airport, thanks to his travel plans being derailed by snow.
He smiled when he met Nato head Jens Stoltenburg in the Soviet-like concrete architecture of the Nato HQ. He smiled when he stood alongside British PM Theresa May in the plush wood-panelled surrounds of 10 Downing St.
Despite the snow and -5C temperatures, English was still smiling when he got to Berlin for his meeting with German Chancellor Angela Merkel - the most powerful person in Europe who dispenses her own smiles sparingly but nonetheless found herself beaming back at English.
It was English's maiden voyage as Prime Minister and the smile helped him dodge the land-mines that awaited. So too did English's confidence.
If he was nervous it did not show - other than forgetting what he ate for lunch at both 10 Downing St and Merkel's Chancellery.
His handling of the press conferences with May and Merkel were not one of a novice.
The trip also showed English settling into the extra responsibilities and accountability that comes with being PM. English has been in politics for 26 years, but there are still unexplored territories in his own belief system.
New Zealanders like to know what drives their leaders. English is acutely aware he is yet to put himself up to the public vote to be PM. So English has started to open up without quibbling about his views on matters from climate change to the monarchy and flag - even though that meant implicit criticism of Key.
English returns to New Zealand a happy man. He might have arrived in a red light district but by the time he had left he had notched up enough green lights to compensate - European Commission president Jean Claude Juncker's estimate of a free trade agreement within 2-3 years might be hopelessly optimistic but to have him say it out loud was enough. Then there was May's own pledge to start trade talks with New Zealand as soon as possible - although English was careful to make it clear to the EU leaders that the EU deal took priority.
The smiling also disguised the difficulty of his tight rope walk in pushing home New Zealand's case on both sides of the Brexit divide without giving any hint of taking a side.
There was palpable anger at the EU about Brexit - starkly shown in Juncker's sharp "no" when English was asked whether New Zealand could get a better deal out of the UK as a result of Brexit.
New Zealand could well simply be a useful tool for both to prove a point - in the EU's case to show it is not paralysed by Brexit and in the UK's to get some early experience on board and show it can cope post Brexit by negotiating its own free trade deals.
Whatever their motives, it is money in the bank for New Zealand - and English will grab it.
