What is sketching and why do it?
A sketch is a fast, free drawing. It is not a finished picture. It helps you observe (look closely), plan a bigger artwork, and record ideas quickly. Art schools ask for sketchbooks because they show how you see and think.
Tools: pencils from hard (H, light grey) to soft (B, dark): HB, 2B, 4B, 6B; charcoal; a putty eraser; paper with a little texture. Hold the pencil loosely and draw from the shoulder for long lines.
Looking and measuring by sight
Choose one part as your unit (for example the height of the box). Hold your pencil at arm's length, close one eye and mark the unit with your thumb. Then compare: "the bottle is 2 units tall", "the table is 6 units wide". Keep your arm straight every time so the measure stays the same.
You can also hold the pencil level or upright to check angles, and look at the negative space (the gaps between objects).
Simple shapes, block-in and line
Break every object into basic forms: box (cube), cylinder, cone, sphere. A bottle is a cylinder; a head is a sphere; a house is a box with a prism roof.
Block in: draw light construction lines: a centre line for symmetry, a base line where objects stand, and ellipses for round tops and bottoms. Fix the big shapes before any detail.
Line quality: use light, quick lines first. Make lines darker and thicker where things are close or in shadow, thinner where light hits.
Light, tone and shading
Tone (value) is how light or dark something is. With one light source, a round object shows five tones: highlight, light, mid-tone, core shadow (darkest part on the object) and cast shadow (the shadow thrown on the table). A little reflected light bounces back into the shadow side.
Shading methods: hatching (parallel lines), cross-hatching (crossed lines), stippling (dots) and blending (smooth tone). Squint your eyes to see the big light and dark shapes.
Quick figure and scene sketches
Gesture drawing catches movement in 30 seconds to 2 minutes. Start with one curved line of action through the body, then add head, ribcage and hips as simple shapes, and stick lines for arms and legs.
Proportion: an adult is about 7½ heads tall. The hips are near the middle; the knees about a quarter of the height from the floor. Children have bigger heads compared to their body.
Scenes: mark the horizon (eye level) first. People standing on the same ground as you have their heads near the horizon. Draw big masses (buildings, trees) as simple blocks, then place figures.
Key formulas and definitions
- Sketching order: Look → Shape → Block in → Shade → Finish
- Pencil grades: H (hard, light) … HB … B (soft, dark); higher B = darker
- 5 tones: highlight, light, mid-tone, core shadow, cast shadow
- Adult figure ≈ 7½ heads tall; hips near the middle
- Line of action: one curve that shows the movement of the whole pose
Worked examples
1. The cup measures 1 pencil-unit tall. The vase is 3½ units tall. On paper the cup is 4 cm tall. How tall should the vase be?
3½ × 4 cm = 14 cm. Keep the same ratio (1 : 3½) between objects.
2. Light comes from the top left onto a ball. Where is the cast shadow?
On the table to the bottom right of the ball, opposite the light. The core shadow is on the right side of the ball.
3. A figure is drawn 30 cm tall. About how tall is the head?
30 ÷ 7.5 = 4 cm. Each head unit is 4 cm, so the hips are about 15 cm from the feet.
Common mistakes
- Starting with tiny details (eyes, buttons) before the big shapes are right.
- Pressing hard from the first line, so construction lines cannot be erased.
- Bending the arm while measuring with the pencil, so the unit keeps changing.
- Shading with no single light direction, so the object looks flat.