Extra long runner rug cover floor areas, where a lot of foot traffic would otherwise damage or floor the existing floor. Carpet stores sell them in standard lengths of standard homes or in large rolls from which you can create your own custom length broker. The difference between a finishing runner and a section of a roll is the cap at the ends of the runner. The lid is the end of the corridor in which the outer edge pattern that extends along the sides, continues through the end, crowning the section. Add at least the width of the corridor for each end you need capped for the total length requirement.
Place your rolled extra long runner rug with the capping end that extends over a work area for cutting. Measure the width of the carpet runner. Cut a section of the corridor from the end, as long as the width of the corridor. Measure with a measuring tape on the back of the corridor on each side using a black marker. Connect the marks with a ruler and a cut through a utility knife.
Cut the side sections that contain the pattern of the cut part. Allow 1/4 inch on the inside of the pattern, cut firmly with a cutter and a ruler. These will be the basis for the end cap. Place the side section on the upper side of the end of the extra long runner rug. The pattern will be perpendicular between the side section and the main corridor; it is not suitable for a clean finish. Look for the upper inner edge of the pattern where it intersects the pattern in the section of cut. Make a mark on the back of the cutting section.