The Hem on Your Trouser
Nothing says sloppy more than a pile of fabric at your ankle. Your pants should reach your shoes and have a slight break. Cuffed or uncuffed is your choice, but keep in mind that cuffless makes you look taller if you happen to be a little shorter and cuffs looks better on someone with long legs. Cuffs also appeal to a more mature consumer.

The Waist of the Jacket
The jacket should fit easily across your stomach. The traditional American cut suit with two buttons, which has been a mainstay for many years, is being replaced by suit jackets which are more fitted and have three and four buttons. However, the classic two-button style remains popular, and some two-button jackets offer a fresh twist with higher button placement similar to the three-button style and is often more flattering. Whether your preferred style is classic or modern, look for fitted waistlines that enhance the shape of your body. Getting a close fit at the waist is, do I dare say it?, a good thing (sorry Martha).

The General Fit of Your Suit
When it is all said and done, you should be able to stretch and bend easily in your suit. Make sure that you that you have free movement of your arms. As a test, bring your arms out straight in front of you, and also try sitting in a chair and pretend you are working. You should always be comfortable.

Buttoning the suit
Double-breasted suits are always kept buttoned. When there is more than one to-button (as in a traditional six-on-two arrangement), only the top one is to be fastened. Often, this is the only one that can be properly fastened, because the bottom to-button often lacks a corresponding interior flap button. In the case of arrangement such as the six-on-one, particularly popular when the double-breasted suit first staged a comeback in the 1980s, one has no choice but to fasten the bottom button as this is the only option.

Single-breasted suits are buttoned while standing. When the jacket is buttoned, all buttons except for the bottom button are fastened. Under no circumstances should the bottom-most button of a single-breasted suit jacket be fastened. This rule is adequate for two-button suits and three-button suits, as well as the rarer four-button suits. Three-buttons suits present a couple of special situations. In the case of three-button suits with lapels that roll over the top button, the top button should not be fastened. These are typically older three-button jackets and contemporary three-button suits are not normally designed this way. With a typical three-button suit made today, one has the option of buttoning only the middle button in the manner of the old three-button cuts, or following the rule of buttoning every button but the bottom-most one. Both are acceptable. To prevent bunching, the single-breasted jacket should be completely unbuttoned while the wearer is seated.

Ties with suits
Working with ties is very much a matter of personal taste, but in conservative terms there are some basic guidelines. Ties should be darker than the wearer's shirt. The background color of the tie should not be the same as that of the shirt, rather the foreground of the tie should contain the color of the shirt and thereby "pick up" on the color of the shirt. Ideally, the tie should also integrate the color of the suit in the same way. Generally, simple or subdued patterns are preferred for conservative dress, though these are terms with a wide range of potential for interpretation. The list of knots generally includes the Four-in-hand, the Half-Windsor (or Windsor), the Full-Windsor (or Double Windsor), and the Shelby or Pratt. A Four-in-hand, Half-Windsor, or Full- Windsor is generally the most appropriate with a suit, particularly by contemporary guidelines. Once properly knotted and arranged, the bottom of the tie should just touch or just go over the top of the belt buckle. The thin end should never extend below the wide end.

Shirts with suits
The type of shirt worn 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 many other dialects of English.

The classic conservative shirt colors are light blue or white, with white edging out as most conservative. The most formal type of dress shirt worn with a standard suit is a shirt with French cuffs, which use cuff links (silk knots can also be used) to close, but this type of shirt is optional, and essentially up to the preferences of the wearer and the vagaries of fashion. Ideally, this shirt should also have what is known as 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 use with a sport coat or without a coat at all. 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. In terms of wear, the shirt should be properly pressed and have collar stays in place if the shirt allows.

Short-sleeve shirts, tennis shirts, and t-shirts should never be worn with a suit when adherence to traditional etiquette is desired.

Socks with suits
Socks should match the pant leg. This makes the leg appear longer and minimizes the noticebility of a too-short pant leg. In the absence of an exact shade match between pants and socks (just the variability of how dye appears on wool and cotton, viscose, silk, et al makes this a practical impossibility), the shade of the socks should always run darker than that of the pants. With patterned socks, ideally the background color of the sock should match the primary/background color of the suit. If it is not possible to match the pant leg, socks may match one's shoes. This is not especially appropriate, particularly in contemporary conservative dress, and should only be done if nothing remotely similar to the pant color can be found. This is only likely to occur in the case of unusual, fashion-forward colors, and there should not be any cause to do this with traditional colors such as navy or gray, barring emergency.

Accessories with suits
Acceptable colors for belt and shoes are black and burgundy/cordovan, though since the 1980s various shades of darker browns (particularly mahogany) have started to gain acceptance. Light browns such as saddle tan and its ilk should be reserved for use with business casual wear. The belt and shoes must match one another, at the very least in color category if not almost exactly in shade. The belt's buckle should be silver or gold. Other metallic objects worn with the suit (such as cuff links, tie bar, tie tack, watch) should match the belt buckle. Where watches are concerned: the more formal the occasion, the thinner the watch. Analogue watches are more formal than digital watches. In the most formal situations, a pocket watch, or no watch at all, should be worn. Generally speaking, one should not wear rubber sole dress shoes, though there are some individual high end shoes that may be exceptions. Leather sole shoes are not only traditional, but more importantly they almost always have uppers that are of a far better quality and have a much more "dressy" appearance. Some companies also make dress shoes with wooden soles.

Handkerchiefs and pocket squares/silks in the upper welt (chest) pocket are not especially common in today's conservative dress, and have never been 'good form' in Britain, though like other accessories (e.g. tie bars), they can certainly be added. Coordinating pocket squares is a matter of taste, but a general safe rule of thumb would be to match the color of the shirt or the background color of the tie. When in doubt, one can simply use the traditional, white cotton or linen handkerchief. There are a number of styles in which these may be folded, all at the wearer's discretion.