Lay the branches on the drop cloth and spray in thin, even coats, turning each branch to coat all sides. Let each coat dry for 30 minutes before adding another. Two coats give a dense, bone-like finish; one coat leaves the bark texture showing more, which also works well. The surface is ready when it looks uniformly pale with no dark patches of bark showing through.

While the branches dry, pack the base of the vase with gravel, sand, or tightly wedged florist foam. This step is essential: tall branches in a lightweight vase tip immediately. The vase should not move when you press the rim with one hand.

Arrange the branches by height, with the tallest at the back and the shortest at the front. Angle them slightly outward rather than straight up for a more natural silhouette. Tuck shorter branches or twigs between them to fill any gaps. The arrangement should look found rather than constructed.