Lightly distress the leather with fine-grade sandpaper, steel wool or a wire-bristle brush. Work in a circular motion. Rub the leather slightly harder on areas where the leather would naturally look more worn, such as where hands touch the armrests or in the center of the seat.
Wipe the leather down with a soft cloth to remove any particles loosened from the distressing process.
Mist the couch with water in spray bottle. This opens the grains of the leather, making it receptive to dyes.
Dip a dauber or sponge into a leather antiquing product. Firms make these products specifically to give leather an antiqued appearance. Begin rubbing the solution into the leather, making small circular motion. Work the product into cuts and grooves in the leather. Completely cover the surface of the couch with the product. Allow it to set for two to five minutes.
Dampen a clean sponge. Wipe off excess antiquing product. Remove it most from raised portions of the couch but leave the accumulation of product in perforations and depressed areas. Allow the leather to dry for 30 minutes.
Buff the entire couch with a clean cloth.
Apply an acrylic-based, water-repellent finish to the leather. Some leather finishes are made specifically to protect antiqued and dyed leather. Apply a thin layer of the product with a damp sponge, working in small circular motions. Allow the product to dry for 30 minutes and remove excess with a clean cloth.