: Use "ghost" lines (barely touching the paper) to map out proportions first.
: Incorporate stray marks into your shading rather than trying to hide them.
Fill the last square as dark as possible using cross-hatching.
: Light touches create faint grays; heavy pressure creates deep blacks. Hatching : Use parallel lines to create basic shadows. Cross-Hatching : Layer lines at angles to deepen values.
Fill the middle squares with increasing layers of ink to create a smooth gradient.