Choose the color you want to dye your chair. Be sure to select a dye that is appropriate for the way the leather on your chair was tanned. In most cases it will be vegetable tanned. If you're not certain, contact the manufacturer.
Clean the leather with a combination of leather bleach and water. Use 1 oimce of leather bleach to 1 pint of water. This will not bleach the leather or change the color, rather it will fade any water spots on the leather.
Dampen the leather with a sponge. Avoid soaking the leather, just keep the surface damp to the touch. This will allow the leather to evenly absorb the dye.
Apply the first coat of dye with a wide brush. Once it has been applied to the entire surface, wait until it dries before adding the next coat. This can take anywhere one to two hours.
Flex the leather once the first coat of leather dye is dry. This will keep the leather from getting stiff in between coats of dye.
Repeat Steps 4 and 5 until the leather is the desired color.
Complete the job by adding a coat of leather finisher. Leather finisher comes in spray cans or bottles. Spray or apply the finisher evenly, and allow it sit for a while until every coat of dye and finisher is dry on your leather chair.