Open a new project or an existing image to create the poster edge line. An existing project will permit a new template to be created by using different colors and shapes. Using an existing image will enable the designer to use colors that match the image.
Create the edge lines using different shapes such as rectangles, ovals and squares. These shapes make it easy to feather the edge of a poster and add a soft effect. Designing thick or thin edges using rectangles and squares also creates a center focal point within the image and produces a clean look to the poster.
Add color to the poster edge lines rather than using a plain, white template. Colored edge lines will highlight the colors within the poster image. Adding color to the poster edge lines will also lend to the theme of a poster, such as those created for Christmas or Halloween.
Place filters over the color edge lines to match the poster's motif. Adding a canvas filter or dust and scratch filter will give poster images an artistic look. Watercolor and fresco painting filters will add a more contemporary style to the poster image.
Design poster edge lines using the paintbrush tools in place of filters. The paintbrush tools permit designers to create edge lines that aren't available in the filter's list. Photo editors produce paint splatters around a poster image or a spray paint look on the edges for an urban theme.
Save the edge line design into a desktop folder after creation. This will make the design easy to locate and retrieve when editing the poster image.