Turn the chair over and examine the bottom to see how it was originally upholstered.
Take apart the chair by unscrewing any screws and pulling out nails or staples with needle-nose pliers.
Remove the old upholstery and lay it flat. Depending on how the chair was made, you may have several pieces of upholstery or just one for the seat cover.
Measure the upholstery pieces. Use these measurements to determine how much replacement upholstery you'll need. Add 1 or 2 yards to your estimate so you have room for mistakes.
Cut the new upholstery to match, using the old upholstery as a template.
Smooth the foam cushions on the chair to make sure they are even with no lumps.
Lay the upholstery on the chair seat and arrange it so it looks nice and is in the same position as the original upholstery. Turn it over so the seat cushion is down.
Fold the edge of one side over and pull it tight. Staple it in position with a staple gun. Staple the opposite in the same manner, with a staple right in the middle of the side. Repeat on the remaining two sides.
Staple along the chair cushion, placing a staple in 1-inch increments until you reach each corner.
Pinch the corner fabric together and cut off 2 inches of fabric with the scissors sloped at a downward angle. Repeat on all four corners.
Gather the corner fabric together so it folds in on itself and puckers evenly. Staple it with three or four staples so it is taut. Repeat on all four corners.
Continue to reupholster the remaining pieces in the same manner, always pulling the fabric taut before stapling it and mimicking the original cover as much as possible.
Reassemble the chair using screws and nails as needed. Replace any worn hardware if necessary.