Above: Nina Ricci

It’s the ultimate July fashion conundrum. Fabulous fall arrivals are making their way into Barneys every day, but it’s still a hot, sticky, 90 degrees outside. It’s not that we don’t love our breezy little dresses and sandals, but summer fashion is, quite frankly, failing to thrill us after all this time. What we need is a little something new.

The challenge? Styling our favorite fall pieces, from a snappy schoolboy blazer to a rich jacquard top, into looks we can wear now—70 percent humidity be damned—and once the temperatures drop to that lovely, crisp, November place…