Here is Your Ultimate Guide Take this matching set from Petal & Pup as an example
Product Features Product Features Button neck closure Asymmetric sleeve design Waist cut out Leg split opening Gathering detail Fitted bodycon Fully lined Maxi length Composition & Care Composition & Care Lining 1: 82% Nylon, 18% Spandex Lining 2: 100% Polyester Wash Care: wash separately before wear, cold hand wash inside out separately in garment bag, do not bleach, soak or rub, do not wring, do not pile wet, do not iron, dry flat in shade, do not hang, do not tumble dry, do not dry clean, jewellery may catch or snag, fabric is delicate, avoid rough or sharp surfaces which may snag, dark colours may transfer to light coloured fabrics and furnishings
Your shoes should be polished and in good condition
A sleek black tux/white shirt is a tried and tested, well-respected combo