This is a drawing question and has no single correct answer; the following approach is what examiners look for.
Option 1 (sketch): lightly block in the overall shape of the bust (cap, head, shoulders, raised hand) inside the frame, fix the proportions (head width to height, eye line at the middle of the head, position of the hand relative to the face) before adding detail.
Option 2 (composition): decode the image into its main elements (head with cap, flowing hair, loose garment with folds, hand holding a pencil) and arrange them in a balanced frame with a clear focal point (the face) and sensible use of empty space.
Rendering: use only black and white techniques such as hatching, cross-hatching, stippling or smooth pencil shading.
Light and shade: keep a consistent light direction, a full tonal range from white paper to dark accents (under the cap brim, hair, folds of the cloth), and soft transitions on the face.
Presentation: clean line quality, no smudges, the drawing filling the frame in a balanced way.