Casual might not call for a tuxedo, but you still want to honor the occasion of two people spending a crapload of money on a party (okay, yes, and vowing to be with one another until the end of time)
Sage Green Long Sleeve Dress Wedding Guest For fall, winter, or cooler-weather weddings, a sage green long-sleeve dress is both practical and elegant
These mainly come from cards - all 4* and 5* cards come with costumes based on the Bloomed version of the card art, with 5* costumes generally being more detailed and Costume Porn-y, plus event 3*s for stories based on actual live performances usually come with them, too
The home stretch
However, if you'd like to try you hand at crazy cat lady made out if silk chiffon, I've seen a green polka dot with kittens
Pair it with a plain tank top or a plaid shirt tied around your waist