Here we've dressed up your well-fitting grey suit for a wedding. French cuff shirt, simple yet elegant cuff links, shoes made for dancing. Don't forget your white pocket square and that dazzling smile.
Acknowledging that it is a thing for people to be outside of the gym in sweatpants, you might want to do that. But please, not sweatpants from 10 years ago, but in an updated, slimmer silhouette. Still comfortable, but now with self-respect.