Ladurée opened at 16 rue Royale in Paris in 1862, and its walls were painted a celadon green that became the house color. Anyone who has walked past one of its shops knows the effect: pale green paint, pastel boxes, and the feeling that you should have dressed up a little.

Sage and pink work the same way on a person. Sage is a gray-green that behaves like a neutral, and pink next to it looks warm instead of sweet. The trick for fall is weight. Swap summer cotton for cashmere, tweed, taffeta and suede, and the pastels stop looking like spring.

A quick test: put a pink scarf on with a sage or olive sweater you already own. If the pink looks soft rather than bubblegum, you have the right pink.

Start with the accessories, since both colors are easy to carry in small doses. Savette's Symmetry Pochette is mint suede with a gold clasp, and Roger Vivier's Gommettine ballet flats are light green patent leather with the buckle on the toe. For pink, &Daughter's Fionn scarf is pale pink ribbed cashmere you can tie like a bandana, and Bottega Veneta's Andiamo clutch is bright pink Intrecciato leather. One green and one pink with a gray coat is all it takes.

Allude's wool and cashmere sweater is a true sage, plain and soft. Alaïa's balloon track pants are pink silk taffeta that puff and gather at the ankle, which makes the outfit feel fun without trying. Christian Louboutin's Cassia 55 pumps are blush satin with a ribbon that ties at the ankle, and Jia Jia's 14-karat gold necklace is strung with small green chrome diopside beads that pick up the sweater.

How to wear it: keep the sweater untucked and slightly long, so the volume of the pants starts below it.

Abadia's draped jersey blouse is a dusty pink with soft gathers at the waist, and Carolina Herrera's tweed mini skirt is a green and white weave that reads sage from a distance. JW Anderson's ruffled suede ankle boots are a soft gray-taupe with ruffles wrapped around the ankle, so the boots carry the texture. Extreme Cashmere's Witch scarf is a pale pink knit you can knot at the neck.

Liberowe's Wren maxi dress is light green chenille with a Lurex shimmer, so it glows a little. Emilia Wickstead's Virginie cape is baby pink moiré and sits at the shoulders like a short capelet. Together they are the most dressed-up look here. Aquazzura's Serenity 85 sandals are mint satin with knotted straps, and Completedworks' agate earrings are green and pink stone drops that repeat both colors at once.

What I would skip: a pink bag. The cape and earrings already carry the pink, and a third piece would tip it into sweet.

Moncler's Iadi parka is a sage green shell with a drawstring waist and big pockets, the practical piece in this lineup. Under it, Jil Sander's wool polo is pastel pink with short sleeves, and Valentino Garavani's cady midi skirt is pink with lace at the hem. Pink on pink underneath and sage on top is an easy formula. Manolo Blahnik's Aliera 50 ankle boots in pale gray nubuck keep the colors soft.

Sage and pink feel right in fall when the fabrics get heavier. Choose a sage with plenty of gray in it and a pink that is soft and dusty, then put them in cashmere, tweed, suede and taffeta instead of linen. Let sage play the neutral and pink play the color. If you only try one look, start with the sage sweater and pink trousers. If you want to keep browsing, I also put together Forest Green and Navy Outfits to Try This Fall and Green and Black Outfits to Try This Fall.