He told us that he’d be back – but, after nearly 60 years in the public eye, Arnold Schwarzenegger has never gone away. Ever since his first trip to the US from Graz, Austria, in 1966, the Terminator has taken on a remarkable number of guises: bodybuilder, action hero, villain and even – in a move that seemed ludicrous in 2003, but in fact foretold decades of politics to come – the elected governor of California.

Arnie’s latest step-change is something more predictable: a “self-help guy”, as he puts it. Twelve years since leaving office, Schwarzenegger has just published his seventh book, Be Useful, sharing his “seven tools for life” and lessons learned in each of his various incarnations. What it does not include, beyond a passing reference to “rock bottom” and an allusion to hurting his family, is his 1996 infidelity when married to Maria Shriver; fathering a love child with his housekeeper; and the more recent allegations of his groping several women, that he apologised for earlier this year. Still, there is plenty in it for anyone keen to match his $450m estimated net worth or enormous biceps.

Supersize your dreams. No, bigger than that

All that stuff about starting small, with realistic goals? Arnie laughs in the face of your puny dreams! He points out that Steven Spielberg didn’t think small. His vision to make movies “was big and broad, like it was for Tiger (golf), Venus and Serena (tennis) and me (America)”. That’s right: growing up in austere circumstances in rural Graz (his father made him do 200 knee-bends every morning to “earn” his breakfast, and was also physically abusive), Arnie’s goal was to conquer not just a continent, but what he regarded as “the No 1 country in the world, as the world’s greatest democracy”. Well … in 2003 he certainly conquered California, at least, with 48.6% of the vote.

Every journey starts with one small step … into a Jacuzzi

Arnie doesn’t deny that change is hard. “But do you know what’s harder? Living a life you hate. That’s hard.” Taking a step towards your future can be as simple as going for a walk in the park, he says, pointing to the solace and inspiration that Wordsworth, Aristotle, Nietzsche and Thoreau drew from daily perambulations: “These are some pretty impressive people.” (Be Useful is not what you might call overburdened with women.)

Arnie found his thinking time between sets at the gym or the “sacred” 10 minutes in the chairlift while out on the slopes. But “these days, I create space for inspiration by taking a Jacuzzi every night”, he writes. “There’s something about the hot water and the steam, about the hum of the jets and the rush of the bubbles.”

It was in these blissful conditions, his neck and shoulders tense “from the stress of the day”, where Arnie “got the idea for my speech to the American people after the [Capitol Hill attack] of 6 January 2021”. This vision, “crystallised in my mind”, led to an eight-minute broadcast on social media, in which he wielded the sword he had carried as Conan the Barbarian and compared its steel to democracy: “The more it is tempered, the stronger it becomes.”

Can you smell the baby oil? Can you see your opponents’ envious faces, the colour of their posing briefs?

“I spent my entire life looking in the mirror,” writes Arnie. He means this figuratively as well as literally, as he watched the box office and ballot box for measures of his performance. He is also, like all self-help guys, a big believer in visualising your goals: picturing yourself on the winner’s podium, hearing the crowd chanting “Arnie! Arnie! Arnie!” and seeing “SCHWARZENEGGER” in big letters on a movie poster, even though it is very long and, for many, hard to say. (You should use your name when visualising your own goals – just to be clear.)

Producers and casting directors pressed him to use a stage name, such as “Arnold Strong”, but Arnie indeed held strong, thanks again to the laser vision of his mind’s eye: “I could see plain as day that Schwarzenegger looks fucking great all by itself in big letters above the title of a movie.”

He was so convinced that 1988’s Twins would succeed, and that he could be a comedic lead, he agreed to forsake his salary to get it made, instead taking only a share of the net profits. Once again, Arnie’s laser sight did not miss: “Twins is still the movie I made the most money on in my entire career.”

Could your sweatpants be blocking your vision of success?

You don’t get the best biceps of all time by paying them only passing attention. Schwarzenegger paid the price for this oversight soon after his arrival in the US. In 1968, he lost his first bodybuilding competition in Miami due to insufficient definition: the American judges, versus European ones, wanted to see the individual muscles, as though “traced out of an anatomy textbook and chiselled from granite”. Although Arnie was bigger and stronger, “I was far too smooth.”

In particular, his calves were sorely lacking according to the proportions of the Grecian ideal. “If you want to be great, you’ve got to deal with your calves,” writes Arnie, in one of his less applicable pearls of wisdom. “Calves are basically the biceps of the legs.”

He realised that he couldn’t risk his puny lower limbs derailing his vision – even bigger than the US now – “to be the best in the world”. So, he writes, “I cut the legs off all my sweatpants so I couldn’t avoid seeing the mirror while I worked out.” A year later, his calves swollen to match his 24in biceps, Arnie ascended to the first of his seven Mr Olympia titles.

The gym is great for life lessons, not just gains

Not all of us may be able to achieve Arnie’s godlike physique, but a lot of the lessons he learned along the way are applicable to us mere mortals. Too many are afraid of pain and failure, he says, and people will go out of their way to avoid them – but they are also a measure of potential and change. While working out, he says, if you can’t feel the muscles being activated, you may not be doing enough to build them: “It wasn’t fun to squat 600 pounds until I couldn’t breathe and wanted to puke. I was smiling because I was feeling the pain of the work.”

Persevering through discomfort builds resilience and character, says Arnie. Equally, if we are content to go to the gym, faff around for half an hour and call it a workout, that can have follow-on effects for the rest of our life. “The person who is OK doing four sets of 10 shitty half-reps on the pulldown machine is more likely to sloppily change their baby’s diaper or forget their partner’s order,” he writes, than the person who struggles through more reps with heavier weights and perfect form.

It comes down to commitment, Arnie says: not just showing up, but following through. In fact, in weightlifting, failure – not being able to squeeze out one more rep – is a measure of success, a sign “you did the work”. “When failure is a positive part of the game you play, it’s much less scary to search for the limits of your ability.”

Arnie is no meathead – he is a fount of wisdom

Though often dismissed as a meathead, in ways that read now as more than a little xenophobic (he describes one late-night show host greeting him with: “You can talk! Oh my God, ladies and gentlemen, he can talk!”), Arnie is generous, thoughtful and thorough in acknowledging the others who helped him to succeed. These range from Krampus, the horned festive figure of European folklore, to his mentor through his teenage years, a Holocaust survivor who coached a group of local boys in Graz in athletics. As well as strength, Fredi taught Arnie to ask questions, be curious and keep an open mind: skills that have stood him in good stead in all his guises.

When Arnie lost his first bodybuilding contest in the US, he invited the victor to stay with him, “so we could train together and he could show me a thing or two”. It is a powerful (and perhaps unexpected) demonstration of being humble in defeat, and success being a team effort. As Arnie astutely notes, self-help and self-improvement can often be used to encourage selfishness in the pursuit of your goals, “used to justify a ‘me against the world’ kind of attitude that turns self-improvement into a zero-sum game”. He’s right, too, when he says that “outside direct athletic competition, it’s almost all bullshit”.

“Life isn’t zero-sum. We can all grow together, get richer together, get stronger together. Everyone can win, in their own time, in their own way.” Arnie concludes that, in a refreshing twist on the self-help genre, the best reason to work on yourself is that you can better help more people.

Today’s politicians make Arnie look pretty good, actually

The value Arnie places on deferring to experts, keeping an open mind and being true to yourself seems to distinguish him from nearly every politician active today. When asked about his historic drug use, he said: “Yes, and I did inhale.” When a journalist tried to shame him, digging up some “wild video I had done for Playboy” in the early 80s, “I simply said, ‘That was such a great time.’ Because it was.”

Arnie’s stories from his eight years in state office find him disdainful of the sniping and snark of political debate; aghast at the extent of partisanship, incompetence and structural inefficiency; and putting his head together with everyone from civil engineers (“I didn’t even know we had that many miles of levees”) to nurses (“the average nurse can’t lift a typical adult male on their own”, although he stops short of offering personal training) to make life better for Californians.

After his 2005 special election blew up in his face, sinking his approval rating to 33% (“lower than George W Bush’s in California, which is saying something”), he told the media and citizens that he took “full responsibility for its failure”. “The buck stops with me.” Can you imagine a single politician today, of any stripe or nation, saying the same?

• Be Useful by Arnold Schwarzenegger (Ebury, £20). To support The Guardian and Observer, order your copy at guardianbookshop.com. Delivery charges may apply.