Turn the kitchen chair upside down and place the seat flat on a counter or table. The back of the chair will hang over the work surface.
Locate the screws that are holding the kitchen chair cushion to the chair. The bottom side of the chair cushion is usually plywood. Unscrew the screws and set aside. Lift the chair cushion off the frame.
Lay the quilt batting on a flat surface. Place the kitchen chair cushion on the batting with the top of the cushion facing down. Cut the quilt batting around the chair cushion allowing enough extra to wrap to the back of the cushion.
Pull the batting to the back of the cushion and staple over the pre-existing upholstery. This should only be an inch or two. Begin stapling in the middle of one side of the cushion back and reverse and staple on the opposite side. This will keep the batting from wrinkling and shifting out of place. Repeat this process for the other two sides. End by smoothing and folding down the corners.
Trim away the excess batting.
Iron the fabric you will be using, removing any wrinkles and creases.
Lay the fabric face down on your work surface. Place the kitchen chair cushion on top of the fabric with the top of the cushion facing down. Cut the fabric around the chair cushion allowing enough extra to wrap to the back of the cushion.
Pull the fabric to the back of the cushion and staple over the batting. Pull up and staple the middle of one side. Reverse and pull up on the opposite side and staple in the middle. Repeat for the other two sides. Miter fold the corners and staple. Continue to staple the rest of the edge.
Trim away the excess fabric.
Place the newly upholstered kitchen chair cushion face down into the chair frame. Poke the screws through the fabric and into the holes of the chair cushion. Use the hammer to force the screws through the new fabric. Re-screw the cushion to the frame.