Stretch a large canvas, old sheet, tablecloth or butcher paper on the grass or tabletop or hang it on the garage or barn door. For an indoor project, cover the floor or table with old newspaper or plastic sheeting. Use construction paper or watercolor painting paper for small-scale projects. You can use wooden or foam craft shapes for decorative ornaments.
Wear old, grubby clothes or a paint smock. Dip a paintbrush into paint and swirl it to coat it thickly. Flick it at the backdrop or let it drip as you wave the brush above the canvas or paper. Alternately, launch paint-covered rubber bands or sponges to create random color splotches. Another option is to dip marbles, string or yarn in paint and roll or drag them across the paper to leave a paint trail. Move around and repeat it with different colors.
Spritz the paper with a water-filled spray bottle or shoot streams of water at the canvas with water guns to create a drip effect. Other water choices include spraying the canvas with a hose or turning a sprinkler on it while you paint.