1. We've said it before and we'll say it again: Fit is everything. Even the world's most expensive suit will look bad if it isn't tailored to the contours of your body.
2. Some think button-down collars are for casual wear only, but they can work great with dressier looks as well.
3. Polka dots are a great way to bring energy to a suit. Make sure they're big enough to be recognizable, but not so large that they're goofy.
4. A tried-and-true pattern like herringbone or glen plaid in a muted shade makes an impression without crossing into the realm of garishness.
Left: Suit ($3,595) by Isaia. Shirt ($550) by Kiton. Tie ($150) by Alfred Dunhill. Belt ($295) by Ermenegildo Zegna. Shoes ($660) by Church's.
5. Visible stitches around the edges of your lapels (called pick-stitching) aren't necessarily a sign of a well-made garment anymore. However, they can be an attractive decorative flourish—as long as they're subtle. No contrast stitching!
6. Some say you shouldn't cut the stitching in your jacket pockets, because putting objects in them will cause your jacket to lose its shape. Don't listen. It's pointless to have nonfunctional pockets, and a concert ticket or a business-card holder certainly won't do any damage.
7. Some think three-pieces are stodgy, but when the waistcoat is cut close to the body and hemmed to the belt line, you'll look slim and modern.
8. Your tie bar should never be wider than your tie.
9. The difference between classic and cliché is often in the material. The timeless appeal of this gray suit begins with its super-luxe cashmere wool.
Right: Suit ($9,900) by Brioni. Shirt ($145) by BOSS Black. Tie ($225) by Isaia. Tie bar ($70) by Paul Stuart. Pocket square ($75) by Polo Ralph Lauren. Shoes ($1,015) by Hermès.
10. Always unfasten your jacket buttons when you sit. No exceptions.
11. Never fasten the bottom button of a double-breasted jacket (unless it has only a single row of buttons).
12. Avoid over-accessorizing. If you're already wearing a pocket square and a tie bar, you'll want to reconsider that clever lapel pin.
13. When wearing corduroy, steer clear of fusty wide wales, but don't go so narrow that the material starts to look like velvet.
14. A dark, patterned pocket square provides a welcome visual anchor to a light-colored suit.
15. When it comes in a sandy tan rather than the usual rust or chocolate brown, this cold-weather suit gets a dose of sunny energy.
16. Save the bulky shock-resistant sports watch for the gym or your outdoor-adventure excursions. It has no place with a suit.
17. Save yourself some embarrassment: Always remove the stitching on the vents and the label on the left sleeve before wearing a new suit.
18. It's fine to flip up the collar of a casual cotton jacket, but when you're dressed more formally (say, in a black suit), you should always leave the collar down.
19. When you go without a tie, it's best to keep your shirt collar on the smaller side.
20. Call attention to special suit material—like this marled wool—by keeping your accessories to a minimum.
21. Tailoring your pants a little bit short will add distinctiveness to your simple look.
ADVICE FROM A SUIT MAKER
Patrick Grant, the owner of the Savile Row fixtures Norton & Sons and E. Tautz, shares his tailoring tips.
22. Get a Uniform
"Men do well when they find something that works for them and stick to it, rather than continually try to reinvent the wheel—one of our customers must have 20 double-breasted jackets in the same cut. If you establish your own sense of style, you don't subject yourself to the vagaries of fashion."
23. You Can't Beat English Tailoring
"I definitely have friends who wear Italian-style suits, which are softer and have less structure. But I prefer English tailoring, which gives suits more shape and a well-defined shoulder. To me, it just looks sharper."
24. Mind Your Silhouette
"You can tell a good handmade suit by looking at it from 50 yards off—it's about overall harmony and balance. The trousers should be slim, the shoulders narrow, the waist nipped."
25. Don't Go Too Short
"A suit jacket should come down to the first knuckle on your thumb. Too many people are cutting short jackets now, and they just make men look too heavy in the middle."
26. Keep Your Cuff Buttons Buttoned
"I think undoing the button on your cuff looks kind of naff. It doesn't signify quality anymore because there are plenty of working buttonholes done by machines."
27. Go For Side Vents
"Most of the suits being made on Savile Row have two vents because it's considered almost cheap work to do fewer. A jacket with one vent or no vents uses much less cloth, and it's much less sewing."
28. Gray-Flannel Suits Always Look Good
"They just work brilliantly with everything. They're elegant without being stuffy and look beautifully luxurious."
PLUS: WHAT TO LOOK FOR BEFORE YOU BUY
29. When your jacket is buttoned, you should be able to fit a fist between your chest and the fabric—no more, no less.
30. Before buying a suit online, try it on in a store first to make sure the shoulders fit, as sizing varies widely among brands.
31. Your jacket sleeves should reveal about half an inch of shirt cuff. If they don't, try a short size instead—you could save yourself a trip to the tailor later on.
32. Choose fabric according to how often you'll wear the suit. The most versatile option is a soft but durable wool like super 120 (a measure of yarn fineness; any higher is too delicate for daily use).
33. Your pants should sit at your waist (not your hips). You should be able to fit one finger into the waistband comfortably.
COATS
Remember, people see your coat before they see your suit. If you've gone to the trouble of putting together the perfect ensemble, you owe it to yourself to finish the look with the right top layer. Whether you want single- or double-breasted, a classic or a bold color, a solid shade or a pattern, there's a well-cut coat to suit you.
34. A double-breasted overcoat should be slim so it doesn't billow when open.
Coat ($4,500) by Hermès. Suit ($3,500) by Dior Homme. Shirt ($195) by Calvin Klein. Tie ($135) by Ralph Lauren Black Label.
35. A slightly cropped overcoat will elongate your silhouette.
36. A pattern is a great complement to a neutral suit.
37. Like a gray suit, a gray overcoat is always in fashion.
38. Navy goes with any suit in your wardrobe—including black.
39. Camel will give you the ultimate luxe look.
Show some personality by mixing and matching patterns and shades—the contrast is what you're after.
RIGHT: Shirt ($335) by Paul Smith London. Tie ($125) by Polo Ralph Lauren
LEFT: Shirt ($295) by Maison Martin Margiela. Tie ($125) by BOSS Selection.
40. Offset a bold tie with a subdued shirt.
41. Modernize your winter knit tie by wearing it with a trim, shortened collar.
42. Two variations of the same color always look good together.
43. When you feel creative, pair dark chambray with a bright, spirited tie.
44. The pattern-on-pattern look is office-appropriate without being predictable.
SHOES
With these updated styles, your biggest problem won't be figuring out how to wear them—it'll be deciding which gorgeous pair to choose.
45. An unexpected color like mossy green will bring out a new dimension in a navy suit. Fratelli Rossetti ($690)
46. The Chelsea boot pairs perfectly with tapered trousers. Banana Republic ($158)47. Worn with a black suit, a black suede captoe delivers a tonal match that will add some texture to your outfit. O'Keefe ($545)48. The black single-monk is the sleekest, most sophisticated, most versatile shoe around.
Church's ($610)49. For a bit of Euro flair, wear a tasseled loafer with pants that graze the middle of your ankle.
Tod's ($625)50. A dark-oxblood shoe is a beautiful complement to a charcoal-gray suit.
John Lobb ($1,640)51. Brogue boots add the perfect rugged touch to your favorite casual suit.
Allen Edmonds ($375)
WATCHES
Don't drag down your outfit with a substandard timepiece—find one that shows you're fully invested in every last detail of your appearance.
52. White face, gold indices, brown leather strap—you can't go wrong.
Movado ($795)53. Oversize, elegantly designed numerals add some panache.
Panerai ($39,800)54. A tank watch, marked by its rectangular shape, spells refinement.
Cartier ($14,200)55. An all-black timepiece is a great match for a solid-black or gray suit.
Bell & Ross ($4,600)56. A watch your grandfather could have worn will look just as great on you.
Omega ($6,800)57. You can wear a chronograph with a suit if it's simple.
TAG Heuer ($5,100)
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