Like ice cream sandwiches, short-sleeve collared shirts arrive with spring and can ruin an outfit if handled incorrectly. Finding abbreviated button-downs that don't look childish has historically been difficult, but designers seem to have spent the winter working on it. One such designer is Timo Weiland, whose label makes shirts designed for casual afternoons watching baseball and grilling.

"The short-sleeve button-down is really at its height; we're making more of them than we ever have before," says Weiland. "It's the perfect piece to wear with nice jeans or trousers in the spring." Indeed, it's a foolproof way to stay casual but also dressed up. While a classic white short-sleeve button-down may conjure up images of Mad Men or the early days of NASA, when all the control-room guys at Cape Canaveral sported them, the modern interpretations are less starched and a lot more stylish. Weiland's short-sleeve shirts have jersey pique sleeves and a soft cotton fabric for the collar and body.

"Personally, I think historically and classically, you wear a simple Hanes undershirt underneath a short-sleeve with a slight roll on the sleeves," says Alan Eckstein, design director at Timo Weiland. "I was just in Nicaragua and every single day I wore a tank top with a short-sleeve buttondown to the beach and then to dinner."

As for what to look for, focus on fabric and the sleeves. A cotton/linen blend will ensure you stay cool and slightly shortened arms will give you a less blocky look. "Arms play a vital role," says Eckstein. Needless to say, the higher you roll, the more bicep you ought to have to show off.

As for whether to tuck or not to tuck, Weiland is a proponent for the latter while Eckstein says it depends on your body. "If you are narrow and skinny and love that body of yours, I think tucking can be sexy and cool," he says. "Or wear it a little more unstructured with the half-tuck." Adds Weiland, "If there's a no-no, I think a tie would be my least favorite."

Keep in mind, however, that short-sleeve shirts are always a little more tailored than regular work shirts. And, when it's buttoned down all the way, your shirt will pull a little bit. Don't worry about that. Overthinking the small stuff is antithetical to your new look.

"It's a quirkier cool, not a self-possessed cool," explains Weiland.