As a co-owner of Odin, one of the best men's shops in the country, Eddy Chai has to be discerning about fashion. That means offering his honest opinion on clothes, even if they happen to come from his younger brother, Richard, who's fast becoming one of the industry's hottest designers. And Richard is happy to return the favor. "If we're critical, it's only because we want the best for one another," Eddy says. "We give each other a fresh perspective." Here, the siblings team up on 10 essential style tips.

"The key to men's style is always being a little undone. You should never look too precious or have colors match too perfectly. And don't be afraid to mix different patterns together, like a plaid with a stripe."—Richard

"The most common mistake men make is not understanding the proper fit of clothes. They're either too big or too small. Buttons shouldn't be so taut that they look like they're going to pop off, and a shirt shouldn't be so loose that it hangs a few inches off the shoulders."—Eddy

"A lot of guys are wearing plaid. To differentiate yourself you have to really think about the tone and scale of the pattern. Go for something with a shot of color, but if you want to tone down the look, layer a neutral V-neck sweater over it."—Richard

"With sportswear, layering is really key. It's more difficult in hot weather but can still be done with breathable fabrics. More and more, designers are using lightweight cottons for button-downs and tees."—Eddy

"Boots were big this past winter, and they're going to be even bigger come fall. They should look natural. I always like the hem of my pants spilling in and out of them."—Richard

"I couldn't survive summer without shorts. When it's humid, trousers just don't cut it. But if you're one of those guys who wear gigantic cargo shorts with stuffed pockets, just say no."—Eddy

"Fragrance can be seasonal. In the warmer months go for something citrus-based. I'm biased—I like Odin 02, which combines Owari mandarin and grapefruit leaves."—Eddy

"Now that it's spring, a good haircut is essential. I get my hair cut once a week at Neighborhood Barbers." —Richard

"You need a pair of simple canvas sneakers that you can bum around in. The collaboration between Tretorn and Comme des Garçons produced some classic low-profile sneaks."—Eddy

"The best way to avoid buyer's regret is to shop when you're not emotional. Coming into Odin is dangerous, because there are always so many things I want. Even with my family discount, it's still dangerous on the wallet."—Richard

THEIR SPRING PICKS
1. Windowpane parka by Richard Chai
2. Cropped wool pants by KZO
3. Sunglasses from Cutler and Gross

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Top Sellers: Odin, New York
Bros Before Clothes: The Burkman Brothers