UMMER PULLS A man to the extremes of the sartorial spectrum in short order: a tuxedo for a black-tie wedding one day, a pair of swim trunks and some espadrilles the next. But at least those situations come with an easyto-follow blueprint. It's the open-ended occasions between the two—vacation dinner outings, backyard get-togethers, a heatwave commute—that present the greatest challenges to warm-weather dressing. The trick is finding items that deliver more structure and polish than tees and shorts but don't cause you to
