Women: Avoid wearing denim, tennis shoes, and cotton tees. Instead, opt for silk pants, dress pants, or a skirt. Pair with a patent leather flat, or one with nice embellishments such as a bow, buckle, or a print.
Men: Wear trousers and a dress shirt with a leather loafer, oxfords, or a slip-on shoe. Pair with a blazer or sport coat. Avoid showing up with wrinkles or clothes one size too big, too small, or in a non-coordinating color. A tie is optional.
When to wear it: Church, Dinner, or an invite received via phone or e-mail.