Clean up the torn area. Cut away loose pieces of leather and any fabric fringes, using sharp scissors. Also pull out any loose stuffing that may be sticking out of the torn area.
Apply a layer of leather filler into the hole. Use the hair dryer to speed up the drying time, and then add another layer of filler. This is a better way to fill the hole and strengthen it from the inside, rather than adding fluffy stuffing.
Apply a small ring of glue around the edge of the tear. Do not let it dry, so work quickly.
Place the sub-patch over the hole. Press firmly around the edges to help it bond with the glue. Do not press on the middle of the patch, only the edges.
Apply a thin coat of leather protector to the patch. Soak a small corner of a soft cloth in the protector and swipe it over the patch in one or two quick motions. Let it dry.
Apply leather color as needed to help blend the patch in with the rest of the leather sofa. Put a small amount of coloring on a soft cloth and spread it evenly over the patch and onto the surrounding leather to help it blend.