Cocktail attire, without the guesswork.

Start with the actual invitation, venue and time. A cocktail dress code at a company reception may call for different coverage from a private rooftop party. If the host adds instructions, follow those before a general style guide.

Consider how you will sit, walk and dance. Check straps, fastenings and any slit in movement. A beautiful garment that needs constant adjustment will make the evening less comfortable.

Try the complete outfit before the day.

Midi and knee-length dresses are familiar cocktail choices, but the fabric and construction still matter. Refined crepe, satin and carefully lined lace can read dressier than a casual cotton maxi. There is no single length that makes a garment right for every party.

If you prefer trousers, try an elegant jumpsuit, a tailored suit or dressy coordinated separates. Finish the outfit intentionally, rather than simply adding jewelry to your usual work clothes.

A trouser outfit can feel just as celebratory as a dress.

Choose shoes you can move in on the actual surface. Dressy flats or a stable low heel may work better than a fine stiletto on grass or cobbles. Check long hems at the height you will actually wear.

A small bag should hold the things you need, not just complete a photograph. For a wedding, avoid an outfit that reads bridal white unless the couple requests it, and check any ceremony or cultural requirements.

The host’s instructions come before a generic fashion rule.