Measure the surface area of the chair's backrest by finding the length and width of its front and multiplying them together to find the front area. Find the length and width of its back and multiply them together to find the rear area. Find the thickness of the backrest and the distance around the edge of the backrest and multiply these numbers together to find the side area. Add these numbers together to find the total backrest area. Repeat this process for the seat.
Cut out a piece of the leather that is a half yard bigger than the total area of the backrest. Set the piece upside down on the seat and slide one edge of the leather into the crack between the seat and the backrest. Staple the edge into the crack with a staple every 2 inches.
Pull the leather tightly up and over the backrest. Make the corners neat by grabbing the corner of the fabric and pulling it underneath the fabric which is hanging on the side, similar to the way wrapping paper is folded. Pull the side fabric down over the corner fabric and pull the side and rear fabric tight to make a clean seam. Fold all of the corners in the chair in this manner to make a uniform result with neat seams.
Staple the sides of the leather tightly to the frame and then pull down the center section to cover these sides and extend all the way underneath the chair. Staple the backrest leather underneath the chair with the staples 2 inches apart.
Cut out a piece of leather for the seat which is a half yard bigger than the measured seat area. Drape the leather upside down over the backrest. Poke just a 1/4-inch of the leather into the crack between the seat and the backrest. Staple the fabric as deeply into the crack as possible, against the wooden frame. Pull the leather down and over the seat.
Make the corners with neat pleats. Stretch the leather tightly over each corner of the chair, pulling it underneath the seat, folding into two pleats and stapling them to the wooden bottom. Remove extra leather with a scissors to prevent a bulky corner.