Line weight — the variation between thick and thin strokes — is one of the simplest tools to add depth, hierarchy, and life to any drawing.

The core rule

Thick lines read as near, dark, or where forms overlap
Thin lines read as far, lit, or where forms turn away
Consistent-weight lines read as flat and mechanical

Where to apply line weight

Situation	Weight
Outer silhouette of a form	Heavy
Where one form overlaps another	Heavy
Cast shadow edge	Medium–Heavy
Interior detail on a lit surface	Thin
Distant or background elements	Thin
Reflected light edge	Very thin

How to practice

Draw a simple object with a single pencil. Start with a uniform outline, then go back and thicken only the bottom and overlapping edges — the drawing will immediately pop with depth.

Next, try using pressure variation mid-stroke: press harder at the start and lift as you finish. This creates a tapered line that feels alive and gestural.

Mindset: Think of line weight as a light source indicator — thick where shadow falls, thin where light hits.