Clean the area that is peeling with a scrub brush dipped in soapy water. Dry the area with a clean towel.
Scrub the area again with a nylon scrub pad dipped in the soapy water. Use small, circular motions. This scuffs up the couch a bit, giving the dye something to adhere to. Wipe dry with a towel.
Wipe down the peeling area with denatured alcohol on a paper towel or clean rag and allow to dry.
Sand the peeling surface with fine-grit sandpaper dipped in the soapy water. This is called wet sanding. Remove any remaining debris with a towel and allow it to dry thoroughly.
Spray your leather prep spray on the area according to the manufacturer's instructions. The spray is usually sprayed directly on the area, rubbed in and wiped off.
Spray your leather dye on the peeling area according to the manufacturer's instructions. Use short, light coats and dry them in between. Use a hair dryer if you have one.
Sand with 400-grit sandpaper between coats if there are still rough spots appearing through the dye.
Repeat spraying the leather dye and sanding two or three times as needed.
Allow the dye to cure for at least eight hours before sitting on the couch.
Condition the leather with a conditioner recommended by your couch manufacturer or with something like Lexol. Conditioning the leather properly will keep it soft and flexible, which can help prevent it from cracking or peeling more in the future.