A bra is essential and should firmly hold the breasts and hide the nipples. A slip or half-slip should be worn unless the skirt is fully lined. Color does not matter unless it can be seen through the clothing. Be particularly careful when wearing unlined light-colored clothes because underwear will show through. They should not be in bold contrast, however.
Silk is the preferred scarf material.
Good scarf styles are the ascot and the scout. Avoid designer goods of any kind, particularly anything with the designer's name or logo visible. If you wear earrings, studs are best. Avoid dangling jewelry. If you do carry a purse, it should be high-quality leather in a dark color.