Reserve several of the squeezed lime halves and chill until ready to serve.
Because chile peppers contain volatile oils that can burn your skin and eyes, avoid direct contact with them as much as possible. When working with chile peppers, wear plastic or rubber gloves. If your bare hands do touch the peppers, wash your hands and nails well with soap and warm water.
Place brown sugar in a shallow dish. Rub a lime wedge around the edge of each glass and dip the edge into the sugar.