Light's bone structure is a dream to model realistically, and I always start by locking down value rather than color. I sketch a clear silhouette and do a grayscale block-in to find the big planes of his face — forehead, cheekbones, nose bridge, jaw — then map the primary light source so shadows fall logically. For that cold, intelligent look he has in 'Death Note', use a harder key light from slightly above and to one side: this creates crisp cast shadows under the brow ridge and nose, and a solid core shadow along the cheek. Treat the skin as layered: soft midtones, subtle warm undertones around the cheeks and ears, deeper cool tones in the occluded areas. I rely on graded pencils (4H to 6B) for traditional work or multiple multiply and overlay layers for digital pieces to build those subtle transitions without losing texture.
For details, I split work into three passes. First, big shapes and values — nothing smaller than a thumb. Second, refine edges and add secondary forms: eyelids, lip planes, hair clumps, and fabric folds in his school uniform. Third, focus on micro-details: individual hair strands, tiny speculars in the eyes, and soft reflected light on the jawline. Use a soft brush or blending stump cautiously to keep pores and texture believable; over-blending flattens the face. For hair, think of ribbons of value rather than countless lines — block in dark masses, then add subtle highlights and a few sharp strands.
A few practical tips from my sketchbook: keep at least one sharp edge around the eye or lips as your focal point and soften everything else; add an almost imperceptible warm reflected light on the neck to separate it from the collar; use an eraser like a kneaded or precision eraser to lift highlights for believable skin shine. If you're working digitally, a final pass with a very low-opacity noise or film grain unifies the piece. I always compare side-by-side with screenshots from 'Death Note' to check expression and lighting; it helps me keep that exact psychological intensity Light carries, which is what really sells a realistic portrait for me.