UNDERSTAND THE TECHNIQUE
Use the long tip deliberately
The dagger brush has a long, tapered, angled shape. Its tip can make a fine beginning. When gently increased pressure brings more of the head onto the surface, the mark can widen. This change is a particular strength of the shape. Start with the handle in a comfortable position and rehearse the movement in the air without paint. This shows whether your hand, paper position and intended curve work together before the first stroke touches your subject.
Get to know the pressure change
The narration describes a progression from a thin line to a broader middle and a narrower end. For your first attempt, keep the head's orientation as consistent as possible and change only the pressure. Touch down lightly, increase contact gently, then ease it again while continuing the stroke. The exact mark depends on loading, consistency and surface. You do not need to press the head hard against the surface to explore the difference.
Choose a mixture that follows the movement
Smooth, workable paint helps with flowing strokes. Paint that is too stiff slows the long tip; an overly fluid mixture can broaden the narrow beginning. Make a test stroke on the same surface as your subject. Fleury lists watercolour, acrylic and oil, recommending a relatively fluid application for this use. Adjust the paint according to the guidance for its binder. Load the head evenly without leaving a drop at the tip. A brief test is worthwhile with each new colour, as pigment and mixture can also change the behaviour.
Develop a leaf from two strokes
The presenter describes two strokes for the leaf example. Begin the first half finely, draw a gentle curve and carefully increase contact in the middle. Reduce it again towards the end. Add the other half with a curved stroke on the opposite side. Whether the leaf is closed or open depends on the path and spacing of the two marks. Leave the first attempt alone and compare both beginnings and endings. A test piece lets you explore the movement before using it in your subject.
Make the brushmark part of the painting
A dagger brush can leave clearly visible movements. This is appealing for expressive plant shapes or decorative ribbons. Decide where those marks should remain visible and where quieter areas work better. A short spotter is more suitable for small, uniform dots. A liner may be easier for long, even individual lines. The dagger complements these shapes where you want to change width deliberately within a stroke.
All sketches show shape and movement direction schematically. The actual paint mark also depends on paint, surface and moisture.