Clean the leather sofa chair with dish detergent, water and a cloth, concentrating on the damaged portion. Dry with a hair dryer.
Apply leather repair compound over the hole or tear, using the applicator included with the compound packaging. Spread the compound about 1/2 inch outside the hole or tear. Dry with a hair dryer set on low, holding it about 8 to 10 inches from the surface.
Wipe the patch with an alcohol swab after drying to smooth it. Dab the swab lightly and do not apply too much or the alcohol might dilute the compound.
Spread leather color coating over the patch with a brush or applicator to make the repair match the rest of the sofa chair. Follow the manufacturer's instructions to get the right color balance. Allow to dry as long as suggested by the manufacturer, then add a second coat if necessary.
Rub leather conditioner onto the patch and over the entire surface of the leather sofa chair with a cloth to clean and treat the material.