A disclaimer before I start. I am a Guardianista. Wiktionary might tell me this term is slang, and derogatory at that, but they know nothing. I hold my badge with pride.

Nor am I the only fan. The Guardian is one of this country’s most respected newspapers. Plummeting circulation figures indicate that it is not immune from the uncertainties facing British print journalism. Yet it is in the process of launching a new digital edition in Australia. And by cottoning on far faster than most of its peers to the world of the web, the Guardian website now attracts an audience of nearly 80 million a month, making it the third most-read online newspaper in the world. An unscientific poll of my housemates revealed that the Guardian was by far and away their online news site of choice. My house is not a bastion of liberalism; the same trend is likely true of yours.

These developments owe an enormous amount to Alan Rusbridger, the Guardian’s editor for the last eighteen years. Rusbridger studied English at Magdalene, and started his journalism career at the Cambridge Evening News, before joining the Guardian in 1979. He has overseen a pioneering change in the paper’s format, a digital revolution, and following its exposés of tabloid phone hacking and Wikileaks, his profile has never been higher.

I meet with him following his talk on Tuesday at the Union. He looks exhausted, and I’m advised by the Union Press Officer that our interview shouldn’t go over five minutes. The man gives me twelve minutes and forty seven seconds, and a chat after over a glass of wine. I’m happy to report he is the complete antidote to the brash Piers Morgan types of the media world: quietly spoken, unassuming, and a nice man to boot.

The Guardian is frequently charged with left-wing bias. “It probably is left of centre”, he accepts when I ask if there is any truth to the claim. “But broadly we’re small ‘l’ liberal. Lots of people who are truly on the left think of the Guardian as part of the industrial complex of capitalism”. The newspaper promoted the Liberal Democrats in the 2010 general election. Given the public derision Clegg and co. have attracted since then, Rusbridger’s faintly cynical aside on that decision -“I don’t know if that’s left or right wing” - suggests some political disillusionment on his part.

The newspaper has never tried to curry favour with any political leader, he insists. “…of the Labour prime ministers Blair didn’t like the Guardian very much, and Gordon Brown ended up not liking the Guardian very much I suspect, and I suspect David Cameron doesn’t like the Guardian very much and probably Clegg is quite disappointed with the Guardian as well. It’s part of the Guardian’s job never to attach itself to any party, but to always question. I honestly don’t wake up in the morning thinking we should be more left or more right.”

Why, then, this enduring stereotype of the infuriatingly self-superior lefty? I quote to Rusbridger a famous statement about the ‘typical Guardian reader’: “a provincial schoolteacher who wore sandals, ate muesli and went on camping holidays in the Lake District”. I spot his eyes narrowing, and pray he doesn’t think I’m taking the piss. A small smile creases his face. “I didn’t say that, did I?” Once reassured otherwise, he proceeds to break down that stereotype entirely. The Guardian’s online content is now three times the size of the Sun’s, he points out, and two thirds of the website’s audience live abroad. “So it’s obviously not a set of people who live in North London and have wispy beards, so that stereotype, I think, is gone.”

The newspaper has for many years run a charity appeal at Christmas which Rusbridger helps to man, and he expresses great pride that among those readers who call up, there is a loyal core, “often northern non-conformists who are teachers and public servants”, united by a progressive outlook. They are, he says, “wonderfully inspiring people”. But the newspaper has got so big – “I hate to use marketing speak – but it is now a global mega-brand” – that the Guardian now has to cater to every kind of individual.

I move on to ask Rusbridger about journalism more generally. How has the training of the journalists the Guardian recruits changed over the near two decades of his editorship? Sites such as the Huffington Post offer an international platform for journalists, a large number of them students looking to make their names known. Should aspiring journalists ever accept to hire themselves out in this way? Indeed, should journalists ever be working for free? Rusbridger does not deliver the impassioned defence of the journalistic trade that I expected. “It’s just a fact of life. I don’t think you can say that should never happen.” The ideal, he acknowledges, is that “journalists earn lots of money and have endless amounts of time”, but, he argues, we have to accept it’s just not so much like that now, and that’s “just something you have to factor into the economics of information in the future.”

What about the diversity of those entering the journalistic profession? The Guardian is vocal about its commitment to seeking out a range of voices. Cases such as the newspaper’s employment of Rusbridger’s daughter Isabella, have in the past prompted sceptical letters from readers about the authenticity of those liberal credentials. Rusbridger does not shy away from the issue when I ask, and clearly promoting diversity is important to him. “There’s a serious risk that journalism becomes a middle-class profession on every spectrum of diversity – race, age, gender, class; that we end up fishing from a small pool.”

What the Guardian does to sort this out though, is a more difficult matter. Almost no hiring is taking place there at the moment: a testament to staff satisfaction, certainly, but also to budget cuts. The media has to make determined efforts at change, Rusbridger acknowledges. There is no option other than to pursue positive discrimination, he says, through means like “work experience, more vigorously advertising jobs, and [thinking about] where you advertise the jobs, and about having positive days off in which you go and find other voices, and other types of people. It’s not simply good enough to wait.”

The future of the Guardian, and journalism more generally, is an uncertain one. These days, Rusbridger spends the bulk of his time in meetings trying to find strategies for this future, not knowing what it may hold. “Some say it’s a gloomy time to be wanting to go into journalism”, he notes towards the end of his talk, “and they’re speaking the truth”. The lucky path he followed from local rag to the nationals is unlikely to work for most aspiring journalists these days.

His advice is twofold. “Everything is a media organisation", he reminded the Union audience. The press office at Burberry, Waitrose, even the University of Cambridge: if you want to write, or take photos, he recommends practice in these establishments first, then working your way into media land.

But more importantly, don’t lose sight of why you wanted to be a journalist in the first place. Whether you’re a writer for the Guardian, the Times; hell, even the Tab: writing is fun, and journalism’s reinvention is there for the taking. Rusbridger’s message? Aspiring journalists of the future: go forth, and revolutionise my trade.