I put this guide together for a recent client to try and demonstrate a beginners guide on what makes items and outfits more casual, gradually going to more formal. It's based on summer wear with some explanations as to what to look out for and other variations you may also want to try. 

From what I hear about how some people dress on Dress Down Fridays, I think this is something a lot of men struggle with, so I hope this is a useful guide, particularly around the middle section where it can get more subtle and therefore complicated to achieve.

1. Very casual

This is pretty much as casual as it gets. The bold print on the shorts makes them more casual than if they were plain and rubber flip-flops are more casual than a leather pair. No need to look sloppy though....tone the colours for a co-ordinated look.

T-shirt: J Crew at Mr Porter £30   Shorts: Incotex at Mr Porter £210   Flip flops: Orlebar Brown at Mr Porter £35

2. Casual - though a little less beachy

The plainer shorts make this outfit a little less casual and it would be smarter still if they were a darker colour. The collar on the polo shirt also makes it a bit smarter as it's a step closer to a shirt, and the closed in shoes are less beachy than flip flops or open toed sandals.

For a fairly casual office, this look might be appropriate for Dress Down Fridays, whereas the first one wouldn't be. If you work in a slightly more formal office or want to wear something like this for a meeting you could smarten it up a little with some deck shoes and a short sleeved shirt or take it up another grade with the white shirt and loafers from look 4. Generally if something has a print on it or it's in a bright colour it makes it more casual than a plain or neutral colour. Other things come into play though so it's not a hard and fast rule.

Shorts: Beams Plus at End Clothing £115 Polo shirt: Unrecorded at Opumo £50 Espadrilles: Oliver Sweeney £99

3. Jeans with casual shirt and trainers

This is a little smarter as it’s more covered up. In general, the darker the colour of the jeans, the smarter they will look. You could replace these with stone or navy chinos which would smarten the look even more. The bold pattern and colour of the shirt makes it more casual but if you were to put in the white shirt from the image directly below it would look smarter. The trainers are also casual but a little smarter than a pair of sport trainers would be.

Shirt: Polo Ralph Lauren at Mr Porter £120 Jeans: Paul Smith £185 Trainers: Jak at Opumo £124

4. Casual chinos, unstructured blazer and loafers

This is definitely going a notch up in formality but the casual washed in soft collar shirt is still not too formal. If the shirt has logos or a button down collar it is also less formal. The blazer is a lightweight seersucker which is unlined so no shoulder padding and the chinos look a little washed in and don’t have a crease in the front so it keeps them casual. The loafers make it a bit smarter or you could wear the white trainers from the picture above if you wanted it to be more casual.

Blazer: Officine Generale at Harvey Nichols £370 Shirt: Save Khaki at End Clothing £135 Chinos: Wax London at Opumo £90 Loafers: Reiss £175

5. Smart chinos or trousers, with formal shirt, blazer and Derbies

This blazer is still fairly unstructured but is a thicker firmer fabric which makes it a little smarter. A blazer is usually shorter than a suit jacket and can have patch pockets and/or texture to differentiate it from a suit jacket. Make sure you have a contrast in colour from your trousers so it doesn’t look like half a suit. Smarter chinos have a front crease aren’t washed in, which makes them more like cotton trousers. The shirt has a stiffened collar which makes it smarter. Shoes with not too much of a tread, and a sleeker design are a bit more formal. These are Derbies not Oxfords which makes them still a little on the casual side.

Blazer: P Johnson at Mr Porter £2,010 Shirt: Chester Barrie at Harvey Nichols £110 Chinos: Oliver Sweeney £89 Shoes: Oliver Sweeney £279

6. Cotton or linen suit with semi formal shirt and casual tie

A cotton or linen suit will be a bit more casual than a wool suit, especially if it doesn’t have much structure or padding in the shoulders. You can wear a slightly more informal shirt, like a button down or a more formal one like the blue stiffened collar one above. A tie in cotton, linen or a knitted tie will balance well with the informality of the suit.

Suit jacket: Solid Homme at Mr Porter £420 Suit trousers: Solid Homme at Mr Porter £225 Shirt: Bluemint at Opumo £90 Tie: Hawes & Curtis £29

7. Wool suit with formal shirt and silk tie

This is the most formal of all (other than black tie, morning dress or white tie). A dark coloured wool suit is more formal than a lighter colour. If you wear a lighter coloured shirt which gives more contrast (ie: white rather than pale blue) it makes it more formal and a classic silk tie. Wear black Oxford shoes with this to tie in with the formality.

Wool suit: Hackett at Harvey Nichols £850 Shirt: Duchamp at Harvey Nichols £90 Tie: Corneliani at Harvey Nichols £95

Here are 3 other useful posts that I came across on the Permanent Style blog which shows you how to switch items in to take an outfit from casual to formal.

Seven Levels of Formality

Colour Combinations: From Casual to Formal

Which Office Are You (Or a Sliding Scale of Formality)

And if you liked this post then you may also like these:

How to Dress For Summer

10 tips on how to dress with gravitas when your office has a casual dress code