As I said yesterday there are a few basic rules we need to follow but and the way in which we see our subject the lighting will change from photographer to photographer.
Loop lighting is a minor variation of Paramount lighting. This is one of the more commonly used lighting setups and is ideal for people with average, oval-shaped faces.
Key Light. To create this setup, the key light is lowered and moved more to the side of the subject so that the shadow under the nose becomes a small loop on the shadow side of the face.
Fill Light. The fill light is also moved, being placed on the opposite side of the camera from the key light and close to the camera–subject axis. It is important that the fill light not cast a shadow of its own in order to maintain the one-light character of the portrait. The only position from which you can really observe whether the fill light is doing its job is at the camera. Check carefully to see if the fill light is casting a shadow of its own by looking through the viewfinder.
Hair and Background Lights. The hair and background lights are used in the same way as they are in Paramount lighting.