How To Ensure A Proper Fit  

Button-down shirts

Shirts divided into more basic areas...

Sleeves & Cuffs
Dress shirts tend to shrink after a few washings, so before buying and getting a shirt tailored, make sure the sleeve is slightly longer in order to counteract any eventual shrinkage. So what's the right length when it comes to shirt sleeves? They should cover your wrist and reach the beginning of your thumbs. As well, your cuffs should be tight enough to prevent them from slipping down your wrist. If you opt to leave your button-down shirt untucked, it should hang just above your pants zipper (at back pocket level). When wearing a jacket and extending your arms, the sleeves should land between a half-inch and one inch past the jacket. Anything longer is cause for tailoring or buying a smaller shirt.

Collars & Shoulders
If the shirt's seams meet at the shoulder, you know it fits quite well. Your forefinger should be able to fit in between your collar and your neck when the shirt is buttoned to the top. The collar's tips and outer edge should be covered by your blazer or suit jacket's lapels. To ensure that this happens, always fit your dress shirts and button-downs before fitting your jackets and blazers.

Blazers
The blazer or jacket's sleeve should rest at your thumb knuckle when your arm is extended, and the blazer or jacket should cover your backside. The blazer/jacket's collar should leave about a half-inch of your dress shirt's collar visible. If you plan on wearing your sports jacket frequently over sweaters, bring a thin or regular knit sweater with you when trying on or tailoring the blazer or suit jacket.

Pants & Trousers
Determining whether you have the right fit when it comes to slacks is fairly simple. Try them on without shoes; they should just touch the floor. With shoes on, the back part of your pants should barely touch the ground (one rule of thumb is that pants should break at about 1/3 of the way down the shoe). And if you need one more sign that your slacks might not fit well, remember that your socks should not show when you walk. When belting slacks, don't pull too tight, or you risk bunching up the fabric around your midsection. This will make your gut appear larger than it is. If you're hemming your pants at the waist, place them below your belly button. And of course, remember that slacks -- like shirts -- usually shrink when you wash them. Buy (or have a tailor create) pants just a shade longer than what you actually need.

Jeans
Jeans, like any casual clothes, shouldn't require any sort of tricky tailoring or complex tips to look right. You should, however, be familiar with the basic jean varieties out there, so that you can make a purchase with your body's best fit in mind. There are three basic jean styles: regular, relaxed and loose.Regular fit is as the name implies; traditional and somewhat slim-fitting. Relaxed fit features an extra half-inch in the butt. Loose fit includes anywhere between one and four inches of additional fabric in the butt and thigh. Jean leg styles include straight, flare and boot. Flare-cut jeans are wider around the calf, while boot-cut jeans are flared around the ankle.

Neckties
The simplest way to ensure a well-fitted necktie is to have a well-fitted shirt to wear it with.Here are some guidelines to remember:
Your tie should always hang barely above your belt buckle. The size of the tie knot should not lift the tips of your shirt collar. The inverted triangle of the tie knot should fit snugly into the triangle created by your buttoned-up shirt collar.

Topcoats & Overcoats
Some resources suggest buying a coat that's one size larger than your suit size, to ensure that it'll fit over your sweaters and suits.Topcoats come in two basic designs: knee-length and midcalf. The coat's sleeve should rest at your thumb knuckle when your arm is extended. The coat's back should be straight and flat, like a suit jacket. Horizontal wrinkles will indicate that the coat is too small. Vertical wrinkles will indicate that the coat is too large, and requires tailoring.

Belts
When it comes to belts, you should buy one size bigger than your pants. A 34" waist means a 36" belt. The buckle's notch should fit into the center hole of the belt (usually hole number three; most belts have five holes). The tail of the belt should end just past the first loop on your pants. The edge of the belt buckle, the row of buttons on your shirt and your fly should all line up vertically.

 
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