You’re not supposed to judge a book by its cover - but in the world of online dating, ignoring first impressions is impossible.

So what aspect of a first impression is most important to a potential mate? According to online dating platform Zoosk, which surveyed 6,646 of its members and analysed over 34,579 profiles, fashion is quite a big deal - often a deal-breaker, in fact.

For singles who consider themselves fashionable, it is a good idea to say so in your online profile - as the survey found including terms like stylish or dressing up can increase incoming messages by 135 per cent.

But if you don’t consider yourself particularly trendy, it may be time to invest in some new duds or a personal shopper because the data found that being unfashionable is a deal-breaker for 54 per cent of women.

Once you get past the profile and into real-life, the first date is crucial when it comes to fashion - as it seems a little, or a lot, of effort is expected from both parties.

According to the survey, 86 per cent of singles say it’s important to dress nice, with 94 per cent of women believing dressing up for a first date is a must.

If fashion really isn’t your thing, at least try to avoid falling victim to one or more of the biggest fashion faux pas.

Wrinkled clothes are the biggest turn-off, according to 66 per cent of singles, with socks and sandals and Crocs following close behind at 55 per cent and 53 per cent respectively.

Always iron before a date as wrinkled clothes are a big turn-off

And baggy clothes circa 90’s fashion are also a no. This also extends to underwear - with 45 per cent of singles reporting that granny panties are a turn-off.

Also, avoid board shorts, dressing too young, pants that are too long or too short, low-rise pants, and super-tight shirts as well - as none of these will earn you any points on a first date.

As for what you should wear on a first date, the survey found that athleisure is having a moment in the dating spotlight - or you could go with the foolproof jeans and t-shirt combo, which 36 per cent of singles say is the best for feeling confident.

Make sure your clothes fit before a date

You can also never go wrong with all-black - a trend that 40 per cent of women revealed makes them feel the most confident and sexy.