The white shirt, in July

Summer's quiet power piece, and how to wear it when it's ninety degrees.

There is a reason the white shirt outlasts every trend: it is the most decisive thing you can put on. In summer, when everyone around you has dressed down to the point of disappearing, a crisp shirt reads as someone who decided. That is its whole power.

The fabric is the difference

In real heat, the shirt lives or dies on the cloth. A fine cotton poplin breathes and holds its line; a washed silk drapes and forgives. Skip anything heavy or synthetic — it will betray you by noon. Cream is often kinder than stark white against summer skin.

How to keep it from looking like work

Roll the sleeves to the forearm. Leave one more button open than you would in winter. Half-tuck it into a skirt or wide trouser, and let a good earring do the rest. Worn this way, the same shirt that anchors a meeting carries a dinner — you simply unbutton your way from one to the other.

Own two: one cotton, one silk. Press the cotton, hang the silk, and you have answered most of summer's wardrobe questions before nine in the morning.