For beginners, **texturing a 3D model** (note: weight painting is a *rigging* step for skinning, not texturing) involves four core steps: UV unwrapping, creating/importing textures, applying materials, and refining details.
UV unwrapping converts the model’s 3D surface into a 2D "map"—like unfolding a cube into a net—so textures align without stretching. Create textures (e.g., diffuse for color, roughness for shine) in free tools (GIMP, Krita) or use royalty-free downloads. Use your software’s material editor (e.g., Blender’s Shader Editor) to link textures to the model. Tweak settings (brightness, gloss) to match your desired look—start with subtle adjustments to avoid overwhelming results.
For newbies, use Blender (free, with tutorials) and practice on simple models (cube, mug) first—this lets you master UVs and textures without complex geometry before moving to detailed projects.