Reupholstering a chair seat cushion is a straightforward process. Lay the cushion on the new fabric, pull the sides up and staple them down. But when you reach the corners, the process is not quite so obvious. However, making professional-looking mitred corners on a chair cushion is not difficult. With just a few simple steps you can create a perfectly smooth corner for your upholstered chair cushion.
Lay the fabric right-side-down on a flat surface. Center the upside-down cushion on it.
Pull the side edges of the fabric up tightly and staple them on the back side of the cushion, 1/2 inch from the edge. Stop 2 inches from the corners. Staple all four sides this way.
Pull one corner of the fabric up and pull it tightly back over the corner of the cushion at a 45-degree angle. Staple it down, 1/2 inch from the corner.
Make a row of small tucks around the edge of the corner from the staple to the side. Staple the tucks down as you go. Pull the fabric toward the centre of the cushion as you form each tuck. This will keep the fabric at the corners smooth and flat.
Make small tucks on the other side of the staple in the same way. Finish stapling the edge of the fabric down on each side of the corner.
Cut off the excess fabric at the corners. Mitre the other corners in the same way.