Beyond shadows, what other techniques can I use to convey texture and grit in a noir comic?

Beyond shadows, consider using cross-hatching, stippling, and scumbling to create texture. The PDF might suggest using rough paper textures or simulating the look of aged newsprint. Incorporating details like cracks in walls, peeling paint, and worn clothing can enhance the gritty realism. Experiment with different pen nibs and drawing tools to achieve varied textures.