Apply a quarter-sized amount of leather cleaner to a clean cloth. Clean the acetone-stained surface to remove any acetone residue along with dust and dirt.
Put on rubber gloves to protect your hands from potential skin irritation caused by the leather preparation solution.
Dampen another cloth with leather preparation solution. Wipe the solution over the bleached area of the leather. Use a dry cloth to vigorously rub the leather surface to open the pores of the leather and prepare it for the dying process.
Dry the leather surface with a clean cloth. Rub fine sandpaper back and forth over the stained leather six to eight times to create a surface the dye can adhere to. Wipe the leather with a dry cloth to remove dust from sanding.
Cut a hole in a plastic drop cloth large enough to provide an open area for the discolored leather. Lay the drop cloth over the remainder of the leather to protect it from splatters or drips of leather dye. Use masking tape to keep the drop cloth in place so only the discolored area of the leather is exposed.
Apply the leather dye to the prepared surface using a sponge-tipped applicator or paintbrush. Use single strokes moving in the same direction to cover the leather with a light coat of dye. Dab the surface with a paper towel to wipe off any bubbles or excess dye. Allow the coat of leather dye to dry completely. Repeat this step until you've applied enough light coats to match the rest of the leather.
Allow your leather surface to air-dry for 48 hours without being disturbed.