Choose a concept for your mural. Possible ideas include community heroes, community unity, diversity, historical greats, world peace, green issues, or other community concerns.
Review principles of design, as offered by sites like the Artist's Toolkit. Books and art websites will give you advice on the use of line, color, positive and negative space, shape, balance, perspective, and movement or rhythm.
Secure any necessary permissions to use outdoor community art space or privately owned space. Many cities have public space designated for art and encourage community members to submit ideas and participate in public art forums and advisory committees. For example, Portland, Oregon's Regional Arts and Culture Council offers opportunities "for artists to engage the public without being concerned about the complexities of a permanent installation." Back in 2005, the Mayor's Committee on Public Art of Louisville, Kentucky, had a designated graffiti wall at a local underpass where community groups and individual artists could create public murals.
Lay plastic drop cloths to prevent paint spills or the defacement of non-approved areas.
Apply a neutral-color base coat to the space with paint rollers. Use a cross-hatch stroke to ensure adequate coverage.
Make several basic sketches of your mural concept on easel paper. Indicate which colors will be used and how much space each element of the mural requires.
Use your concept sketch as a guide to make a larger, freehand sketch of your mural design on the space. Use chalk or charcoal briquettes to sketch a rough outline that includes every element of the final mural.
Place sawhorses or other physical barriers around the mural space to avoid foot, bicycle, or other traffic from interfering with the work as well as prevent any health or safety risks.
Provide adaptive equipment, such as extension wands, wheelchair-size paint smocks, and arm, wrist or hand supports to anyone using a mobility or support device so that the mural space will be completely accessible to all.
Use wheelchair-accessible hydraulic safety lifts to give people using mobility devices access to upper portions of the mural.
Designate sections of the mural to each participant and provide each with a copy of the concept sketch. Assist participants as needed as they paint each portion of the mural. Outline mural elements with black paint if your concept has an urban-graffiti, pop art, or modern art style.
Paint the lightest color areas of the mural first. Let each section dry completely before you apply another color in or near that area. Working from light to dark will reduce the need to clean brushes after every color change.
Have participants initial the mural where they painted.
Once the mural has dried, apply three to five coats of clear weatherproof sealant to the entire project to protect it from sun, wind, and rain damage.