A semi-formal dress code asks for something polished but short of black tie, whether that is a midi, a fluid maxi or tailored separates in a colour with some personality. When in doubt, dress one notch above what the invitation suggests. These four accessories work with every dress below: a bead-embellished Dries Van Noten clutch, Jimmy Choo's gold crinkled-satin Sacora sandals, Saint Laurent's gold Feuilles earrings and Bernadette's embroidered velvet cherry pouch.

A strong colour does the job of jewelry at a semi-formal wedding. Ulla Johnson's pink strapless duchesse-satin Cosima midi and Abadia's chartreuse silk-satin Quinn midi are the brightest here, Valentino's cobalt silk-blend jacquard midi adds pattern, and Dima Ayad's orange sequin mesh midi handles an evening reception. Keep the accessories gold and simple so the colour stays the headline.

The satin slip is the most useful semi-formal dress there is, because it reads differently depending on the shoe. Zimmermann's chocolate draped silk satin maxi, Sharon Wauchob's black draped silk-satin maxi, Aflalo's green silk-satin Aire maxi and La Ligne's taupe draped satin midi with a flipped lapel all keep the line long and clean. Add the gold sandals for evening and a flat for a garden ceremony.

Black works at most semi-formal weddings, as long as the dress has a detail worth looking at. Alaïa's ruched velvet midi has crystal embellishment, Bottega Veneta's knitted maxi comes with chain details, Vivienne Westwood's chiffon midi is flocked with polka dots and Missoni's ribbed-knit maxi is covered in sequins. Each one does the dressing up on its own.

Draping flatters almost everyone and forgives a long day of sitting. Brandon Maxwell's burgundy one-shoulder jersey Mila maxi, Tove's red gathered satin Coco maxi, Isabel Marant's navy twist-front silk-satin Delfi midi and Toteme's dark green draped crepe satin maxi all rely on fabric manipulation instead of embellishment. They pack well too, which helps for a destination wedding.

Semi-formal is the easiest dress code to get right and the easiest to overthink. If you take one thing away, let it be that fabric and fit matter more than length, so choose the dress that moves well over the one with the most going on. We would skip anything white, cream or pale enough to photograph as white, and anything so sparkly it competes with the wedding party. A slip or a draped dress in a colour you love will carry you through several weddings with a change of shoes and earrings. If the venue is outdoors, bring a flat for the lawn and save the heel for the dance floor. If you want to keep browsing, I also put together Garden Formal Wedding Guest Dress and Wedding Guest Dresses.