The edding 5400 acrylic 3D double liner can be either used directly on various surfaces (preferably on surfaces like canvas/paper/wood) for 3D effects, or the paste can be diluted with water and applied with a brush as common for acrylic paint.  Furthermore the edding 5400 3D double liner comes with two different nozzles to distribute the acrylic paste in various ways. For tips and techniques see https://www.edding.com/ideas/manuals/acrylic-basics/tips-and-techniques/ .