"Bleeding the edge" was a term that I came upon many years ago, and ever since it has allowed me to consider very carefully how my artwork extends to the edge of the composition. For those unfamiliar with the phrase, the term "bleed" is a printer's term that refers to the part of a printed image that extends slightly beyond where the image is trimmed. Having a bleed ensures that the image extends to the edge of a poster, page, flyer, or card without leaving any odd white edges.
Imagining a journal page or a canvas with a bleed allows me to envision the lines, shapes, and images extending to the edge of the work. It helps me divide the space of the work into smaller, yet more visually interesting spaces.
I've even made it into a bit of a drawing game. There is just a single rule, and it works for a canvas, a panel, or a page in the journal. The rule is each line that I draw has to begin at the edge and end at an edge. It can be the same edge, or it can be a different edge. The lines can crisscross, or they can stay separate. In either case, I can experiment with the way the image, the lines, and shapes fill and divide the space. For me bleeding the edge is a simple, yet effective compositional device.