For a long time, the most expensive thing I owned was a pair of shoes, but that didn’t stop me filling every shelf and drawer with cheaper bits and pieces. Last year, I read Marie Kondo’s The Life-Changing Magic Of Tidying (Vermilion, £11.99). In it, Kondo claims we can all live happier lives if we tidy up the environment around us. She suggests that we audit our possessions by holding each one and asking, ‘Does this bring me joy?’

It sounds bonkers and, to be frank, standing in my living room holding a dress in my hands and asking the question out loud, I felt like a bit of an idiot. But the funny thing was, I knew the answer was ‘no’ straight away and I had no problem throwing the offending item into the charity-shop pile. Creating literal space somehow also created mental space. I’d let go of things I thought I treasured and found I didn’t miss them; could this also work for other aspects in my life? Was it time to say goodbye to some old beliefs, too?

Not all of our baggage is physical. It’s one thing to admit we have no more space left in our cupboards, but something else to let go of the thoughts and ideas that have guided us through life. Our minds are funny things; we hear something once and believe it as truth. Then, we spend our days looking for ways to confirm this. Most of the time, though, these thoughts relate to who we used to be, not who we are now. We need to say goodbye to them in the same way that we’ve said goodbye to teenage crushes and old school books. It’s easier said than done, I know, but the first place to start is with the simple question, ‘Is that a true statement?’

I once worked with a coach who did nothing but ask this for an entire hour – and it was intense. Try it. Each time you hear yourself say something as fact, just ask, ‘Is that a true statement?’ Warning though, it will make your head spin. For me, it was the phrase, ‘I look after myself, nobody else can’, neatly blocking anyone from getting too close. For a friend of mine it was, ‘Nobody will love me unless I’m thin’, which justified her extreme diet. If you’d asked either of us to explain why we believed these phrases, we wouldn’t have been able to tell you, but somehow they’d been drilled into our minds. It was only when we realised that they were automatic, rather than real, that we began to let them go.

But you can’t just hand a belief to a charity shop as you would an old pair of trousers. Instead, you need to look at what it has given you: be it safety, confidence or a set of rules to live by. Then say, ‘Your work here is done and I’m letting you go’. Enjoy the space you’ve created and move on.

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Photograph: Mark Harrison for Psychologies