Lay the dried flowers on the drop cloth and spray in thin, light coats, turning the stems to reach all sides. Dried material is fragile, so hold the can at least 40 cm away and use less pressure than you would on a solid surface. Let each coat dry for 20 minutes before adding another. The stems and petals should look fully black with the original texture still visible, not crushed or matted with paint.

Cut the floral foam block to fit snugly inside the vase opening and press it in firmly. It should sit about 2 cm below the vase rim so it does not show. If the foam is visible, press it down further or trim the top with scissors.

Begin arranging with the three tallest stems, placing them toward the back and at varying angles. Add medium stems to fill the mid-section, then shorter pieces at the front to cover the foam. The arrangement is done when no foam is visible and the stems sit at three or more distinct height levels.