How can I effectively use a rim light in a portrait to enhance the subject's features and create a striking visual impact?

To effectively use a rim light in a portrait, position the light behind the subject to create a glowing outline around their silhouette. This technique helps separate the subject from the background, adds depth to the image, and highlights their features, creating a visually striking effect. Adjust the intensity and angle of the rim light to achieve the desired look and enhance the subject's appearance in the portrait.