Break the rules: go wild! Wear wide-leg trousers, cropped trousers, or no trousers at all. Buy a t-shirt with a faux-Nike swoosh that says 'Corbyn' underneath and wear it with tiny sunglasses, cargo pants and dad trainers... original! Enjoy the flux, the switch-up, the sharp scissors of change slicing through the dusty fabrics of #menswear...

....just don't forget the exceptions. The unchangeables. The rules cast in stone. Because for all the radical changes infiltrating the way men dress today, there are still some rules that everyone - yes, even you - will benefit from following.

These are the 10 must-obey principles of dressing well. Disobey them at your peril.

The Proper Way To Button Up A Blazer

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Be less Leo

Ok, we're going to get this one out of the way early because it still seems to cause a lot of confusion.

Here are the correct ways to button up each style of blazer.

The One-Button Blazer

Buttoned while standing; unbuttoned while sat. You don't want to stretch that fabric.

The Two-Button Blazer

Only the top button. Never both.

The Three-Button Blazer

Sometimes fasten the top button (if you're feeling it), always the middle button and never the bottom.

Never.

The Double-Breasted Blazer

Generally-speaking, you fasten every button on a DB save for the bottom one. But then again some stylish men have taken to fastening every button, which is fine as long as the cut of the jacket suits it.

Also, keep it buttoned while sat down.

Square-Toe Shoes Are (Always And Forever) A No Go

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You know the drill...

We wonder whether the designer who dreamt up the laceless, square-toe dress shoe - preferably in a shade of brown that could be mistaken for orange - ever jerks awake in night, drenched in cold sweat. Do they stare into the abyss of their lonely bedroom and see shapes forming? Do they ever think about all the men that have been stricken with the square-toe curse down the years. Do they ever regret what they've done? Do they feel responsible?

No Novelty Ties, Socks... Or Anything

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HAHAHAHA

A rule of thumb to follow here is that if a kooky New World prime minister thinks that it's a really cool and hilarious PR move to wear socks with Chewbacca's face on them (yeah we're looking at you, Trudeau), then you should steer well clear.

Clothes should never be that fun.

Waistcoats Are Not A Statement Piece

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A waistcoat should only ever be worn as part of a three-piece suit. Leave the 'statement waistcoat' to mixologists, dodgy pub magicians and those chinless guys from Mumford and Sons.

Are they still around?

If You're Undoing More Than Two Buttons On Your Shirt Then You Better Be An Italian Billionaire...

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... Or Mick Jagger. And even if you are (congratulations by the way, signore or Mick), one should always maintain a keen awareness of the dangerously fine line that runs between raffish dandy and desperate sleaze ball. Because, super yacht or not, does the world really need to see that much man chest?

Don't Wear Jeans With Blazers

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NOOOOOOOOO

Do you host a now mostly-irrelevant motoring show? Are you trying to evict a pensioner from her central London home so that you can sell off the real estate for a huge mark-up to a murky Russian conglomerate? Do you describe yourself as both a "dreamer" and an "entrepreneur" in your Linkedin profile? If the answer to any of those is yes, then we're sorry, we can't help you. If the answer is no, then you really, really shouldn't wear a blazer with jeans. It's not 'smart caaaaaj', it's sloppy.

No Vests... Even To The Gym

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Sorry, Becks..

Even if you're massive. Even if the gains are huge. Even if you have an abnormal condition that makes you sweat like a bison during a Colorado summer (especially then!). Vests are for 2003-2010-era Rafael Nadal, small children who live by the beach and guys who think that other people care about their gym routine.

No one cares about anyone else's gym routine.

Don't Skimp On Shoes

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Cillian Murphy in a pair of very nice monk straps

Cliched as it may sound, while people generally only care about themselves, they do care about what shoes you have on your feet (especially women), which means that you should - where you can - spend a bit of money on them.

That doesn't mean you have to take a pilgrimage to Northampton and bend the knee to some master cobbler, but it does mean that you should reevaluate those £29.99 brogues.

If they cost less than that round you were (passive aggressively) forced to buy for some colleagues one Thursday after work, then you're only playing yourself.

Don't Match Your Tie With Your Pocket Square

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Unless you want to like you're doing your mum a favour by wearing that 'formal set' that you swore you really loved at Christmas, then don't coordinate your tie and pocket square. Complimentary colours are one thing, but obsessively matched patterns will make it look like you've watch American Psycho just a few too many times.

"Would you like to hear today's specials?"

Forget (Most) Style Rules

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Excluding the above, which are sacrosanct, the most important style rule is to relax. Consider your outfit, but ultimately trust your instincts and make sure you enjoy both what you wear and how you wear it. Because for every hard-and-fast rule out there, you can guarantee there's one guy who's making the opposite work for him.

Except for the novelty socks.

Headshot of Finlay Renwick
Finlay Renwick
Deputy Style Editor
Mother, blogger, vegan, model, liar