5 Style Mistakes to Avoid at a Restaurant in Summer Trousers with a shirt was too much to ask, right?

In this era of "I'll wear what I want," it's common to place the importance of self-expression above the norms of social decorum — especially when dining out. How many times have you walked past the outdoor terrace of a nice seaside restaurant in the evening and spotted the inevitable American tourist dressed as though they're about to climb a mountain, in a t-shirt and technical sandals? Some will say that as long as someone pays the bill at the end, they can wear whatever they like — it's their business. But that's not how it works.

Far be it from us to sound like Alain Elkann on the train to Foggia, but it must be said that seeing people in swimwear, worn-out t-shirts, and wraparound sunglasses at a refined seaside bistro not only poisons the vibe of the entire room, but could also undermine the pleasure of savouring a fresh prawn or a plate of spaghetti alle vongole. There is simply no excuse for being slovenly: no one should ever find themselves in the position of being told, as in the famous scene from Mad Men, "it doesn't take money to dress better than you."

Before anyone reaches for torches and pitchforks, a disclaimer: we are talking here about evening attire or a formal lunch — your casual bite at the beach shack can absolutely be eaten in your swimsuit.

Here, then, are 5 style mistakes to avoid at a restaurant in summer.

1. Those wretched toes

The logic is simple: however welcoming it may be, a restaurant is not your back porch. But there's another consideration too: no one, while eating, should have toes in their field of vision. While a delicate sandal is permitted for women (and women tend to pay sufficient attention to their pedicure), it is inadvisable for the rest of the world. Want to eat oysters in Birkenstocks? You're perfectly free to do so, just as others are perfectly free to judge you. Want to go in rubber flip-flops? There ought to be a law against it.

The only exceptions: if the sandal is objectively extremely elegant (if it has Velcro straps or is made of synthetic material, it is not extremely elegant, by the way); if the pedicure has been executed with the precision of a surgical procedure; if the overall look is entirely beyond reproach.

2. Keep those deltoids in check

With the boom of gym culture and the wave of Metrosexuality 2.0 embodied by Ryan Gosling's Ken, a large number of young men — with the boldness typical of their age and that sense of mechanical, uncritical rebellion against social convention — have taken to showing up at restaurants in a vest.

Now, granted that a vest can be rather sexy in more informal and divertidos social settings, wearing one to a restaurant is a bit like wearing sneakers to a wedding: perhaps you have nothing else in your wardrobe, perhaps you think the rules don't apply to you, perhaps you feel "modern," perhaps you simply don't know how to dress. A vest worn under a shirt is just about acceptable, but in general, no one wants to see your armpits while eating their fish entrées — or worse, the two-day regrowth from your last wax.

3. The wrong shorts

Unlike others, we won't tell you that shorts are universally wrong. But there are shorts and there are shorts. A pair that isn't too short, with a nice pleat, in a refined fabric and colour, can pass muster for a dinner near the beach or one that isn't too formal — provided the legs wearing them are reasonably presentable. However, any shorts that are even remotely sporty, or feature cargo pockets, drawstrings, or dangling embellishments, are absolutely slovenly. There's no way around it: even worse if they fall below the knee like a pair of three-quarter-length trousers — no restaurant is so informal as to deserve such an outfit.

If you're struggling to decide on this particular point, use the Gianni Agnelli method: ask yourself, "Would Gianni Agnelli have worn them?" If the answer is no, well, there's your answer.

4. The baseball cap

Let's see. You're a teenager, or an adult who feels young; growing up you listened to all the hip-hop you could get your hands on, and the essence of your style is one of those baseball caps that, back in the day, 50 Cent or John Cena wore with casual insouciance. Alternative scenario: you've looked at one too many "Old Money Aesthetic" mood boards and convinced yourself you're some member of the Kennedy family on holiday in Hyannis Port or strolling the streets of New York — or perhaps a devotee of Ralph Lauren in the '90s. In any of these cases, you might think that wearing a baseball cap to a restaurant is acceptable, even youthful and cool. You are wrong. One eats with one's head uncovered. Full stop.

5. The Hawaiian shirt

You're finally on holiday, you're feeling ironic and alternative, and you decide to wear a Hawaiian shirt everywhere you go. On the beach? Perfect. Out dancing? Potentially fun, though you'll need to pull it off yourself. To a restaurant? Go directly to jail, do not pass Go.