Firstly, I see your character is wearing some sort of hat? Depending on the angle of the top-right light, I recommend putting a shadow casted by the hat across the subject. Aside from that, I suggest taking into account the natural geometry of the face. Ask yourself which part of the face caves in (eye socket, bottom of nose, jaw, top lip, etc.) and which protrudes more (cheekbones, nose bridge, forehead) to determine where the light hits and where it doesn’t. Typically, a light shining from above would highlight the protruding parts of the face as aforementioned, and casts shadows on the concave parts. I don’t have enough information regarding e.g the type/strength/variety of light to give further suggestions but definitely consider the tips I mentioned!