If anyone knows how to pack for an adventure, it’s Mr David de Rothschild. By his late twenties, the explorer had journeyed to both Poles, (becoming the youngest Briton to do so). He has sailed from San Francisco to Sydney on Plastiki, a catamaran of his own devising made out of 12,500 reclaimed plastic bottles, and traversed the Ecuadorian rainforest to document the devastating environmental impact of oil drilling in the region. All before the age of 40.

Packing for such excursions depends on myriad variables, the weather being the most obvious, but, he says, you’ll never be able to pack for every eventuality. “If you’re prepared for everything, then you’re missing a little bit of the spontaneity and the magic,” he says. “Nothing goes right the whole time. I think half the fun is when experiences unfold because of circumstances out of your control.”

When you’re setting off on any journey, you should think hard about what you actually need, he advises. “It’s not so much about travelling light, but travelling smart,” he says. Here’s how a pro does it.

“The essential that I never, ever travel without, or I feel lost if I forget, is a handkerchief. I would say that has been on every single one of my trips,” says Mr de Rothschild. Its uses are endless. “It’s a bandana for your head if you’re hot,” he says. “You can dip it in river water and wrap it around your neck to cool you down. You can wrap cuts in it. If you spill something, you can mop it up. You can blow your nose, obviously. If you sprain your ankle, you can make a compress with it. You can wash with it. You can clean your glasses with it. You can wrap your valuables in it. You can even make a cup of tea in it.”

This is non-negotiable, according to Mr de Rothschild. “It doesn’t matter if you’re just walking to the beach, let alone climbing up a mountain,” he says. “If you go out there on day one and hammer your feet because you’ve just bought a brand new pair of shoes, you’ll get crippling blisters so you can’t walk.” There’s a misconception that you always need a pair of heavy-duty hiking boots. “Don’t over-engineer your feet,” he says. “They’ve evolved over 300,000 years and they know what they’re doing.” The right socks, too, make a difference. “Don’t go for things that are too thick or too tight,” says Mr de Rothschild. “A pair of really good light merino wool or cotton socks is best.”

The versatility of sweatpants or a hoodie makes them a godsend for serial over-packers. “We think we need an outfit for the gym, an outfit for the evening, then we need an outfit for the beach and then we might need an outfit for playing tennis, then we need an outfit if we’re going to go for a hike,” says Mr de Rothschild. “Today, you can kind of get away with wearing the same thing in all those situations.”

“Another misconception is that you need a really big jacket if you’re going somewhere cold,” says Mr de Rothschild. Layering is much more effective and important. He recommends choosing an outer shell that’s extra lightweight, such as Patagonia’s Houdini jacket, a waterproof windbreaker that packs into itself. The brand’s sustainable practices earn plaudits from Mr de Rothschild, too. “It’s not compromising on style or quality of materials and obviously not compromising on its values,” he says.

Apart from a really good reef-safe SPF, which is especially necessary if you’re travelling to a mountainous region or swimming in the ocean, streamlining your grooming regimen helps maximise space, says Mr de Rothschild. His own brand, The Lost Explorer, specialises in this kind of thing. “The Everyday Skin Support Balm is an all-rounder,” he says. “It’s for everything from chaps, burns, bites and rashes.” He also stresses the importance of using natural ingredients. “One of the biggest issues we face now when we travel is pollution,” he says. “Minimising our exposure to chemicals is important, so make sure you’re using things that aren’t just adding more toxins to your over-stressed system.” The added bonus is that you won’t be polluting your environment, either.

Not everything you pack has to serve an obviously practical purpose. Carrying a hip flask, for example, is a great way to make new friends. “You’d be surprised how many times I’ve turned up in remote places and I’ve offered someone a little bit of whisky or mezcal and it just completely changes the relationship you have with someone,” says Mr de Rothschild. “You instantly bond with someone.” And don’t leave home without a pack of cards. “If you learn a few magic tricks, it always goes a long way when you’re in a new country, meeting new people and want to break the ice,” he says.