The type of shirt worn by men with a suit is a top made of woven cloth, with long sleeves, a full-length buttoned opening down the front, and a collar. This type of garment is known in American English as a dress shirt but simply as a shirt in other English dialects. This type of shirt is sometimes called an Oxford shirt; however, this properly refers to a shirt made from a specific kind of fabric, namely Oxford cloth, in a specific style (i.e., with button-down collars).
The classic shirt colours are light blue or white, with white considered most conservative. However, numerous colours and shades are available, with pastels particularly popular in America, though less-formal colours are not always acceptable. Light blue shirts are traditionally favored on television because white can often appear too dazzling on screen and makes suits and ties look darker than they really are; whereas light blue makes skin look ruddier and healthier by contrast. The most formal type of dress shirt worn with a standard suit is a shirt with linked, but not French cuffs, which are closed using cuff links or silk knots instead of buttons. However, this type of shirt is optional, and essentially up to the preferences of the wearer and the vagaries of fashion.
The most traditional collar is a spread collar. This is frequently the default collar type for French cuff shirts, though they can sometimes be found with point collars. Normally, button-down collars are reserved for casual use with a sports jacket or without a coat at all, though they have long been acceptable in America. The button-down collar is not seeing as much wear today, particularly with the resurgence of more formal shirts with spread collars and French cuffs, even in business casual wear. Also it should be noted that at-least 3/4th of an inch of the cuff of the shirt should be visible under the cuss of the suit's sleeve to show a mark of a well groomed personality.
Socks with suits
In the United States it is common for socks to match the trouser leg.This makes the leg appear longer and minimises the attention drawn by a trouser leg tailored to be too short. A more general rule is for socks to be darker than the shade of the trousers, but potentially a different colour. With patterned socks, ideally the background colour of the sock should match the primary colour of the suit. If it is not possible to match the trouser leg, socks may match one's shoes. In particular, pale or even white socks might be worn with, for example, a cream linen suit with white shoes. Although white socks may be worn with very light coloured suits, it is less common and considered a faux pas with darker suits. In practice therefore socks are usually navy, black, or brown, particularly for more conservative occasions.
Socks are preferably at least mid-calf height (over-the-calf), if not knee-height, and are usually made predominantly of cotton or wool, though luxury or dress socks may use more exotic blends such as silk and cashmere. Before WWII, patterned socks were common, and a variety of designs like Argyle or contrasting socks was commonly seen. After WWII, socks became more subdued in colour.
Accessories with suits
A pinstriped navy blue suit, with a grey one in the background, necktie and pocket square.
Belts come in and out of fashion; at the turn of the century and in the 1930s–40s they were worn less than braces (suspenders), but now are generally worn more; in some countries such as the UK, traditionalist men still do not wear belts with suits. If worn, the belt and shoes must be roughly the same colour, with the belt a smart one (leather, plain silver or gold coloured buckle). Braces are often worn if a belt is not.
Jewelry should be kept to an absolute minimum, consisting at most of cuff links, tie bars or tacks, and a timepiece. The thinner the watch, the more formal, and analogue watches are more formal than digital. In the most formal situations, a pocket watch, or no watch at all, should be worn. When worn, a pocket watch is not placed in the trouser pocket, but usually accompanies a waistcoat. In this case it may be carried in any of its pockets, but commonly where it can be easily accessed, such as a left pocket for a right-handed man. The watch is not carried loose, but is attached by a watch chain, which is threaded through the watch-hole: on traditional waistcoats, halfway down is an extra horizontal hole, not intended for a button, which is meant to be used for the watch chain; if no such hole is present, a buttonhole is used instead. A chain normally has one or two ends, the first of which attaches to the watch, the second holding either a decorative fob or a key for winding the watch; a bar in the middle catches on the buttonhole, holding the watch if it is dropped. Pocket watches are occasionally placed in the breast pocket, secured to the lapel buttonhole.
Handkerchiefs (pocket squares) in the upper welt (chest) pocket are not especially common today. Originally, handkerchiefs were worn partially protruding from the left jacket sleeve. Over time, they migrated to the breast pocket. When silk was still a rare and expensive commodity, they were considered a flamboyant extravagance by conservative commentators. By the end of the 19th century, however, they had become a standard accoutrement for gentlemen, and in some places are still considered obligatory on any jacket or coat with a breast pocket.
Source : Wikipedia
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