Evaluate the severity of the tear. If stuffing is exposed and the tear is more than 2 inches long, you must sew the sides back together before applying a leather repair compound. If the edges of the tear are jagged, sewing may do more harm than good.
Push exposed stuffing back into the couch, and align it accordingly. Failure to spread the stuffing evenly beneath the faux leather will result in a lumpy, uneven seat.
Thread a leather needle with waxed leather thread, and then tie a large knot in the end. Leather needles are designed to puncture leather and make small incisions to ease movement. Waxed thread glides easily through the holes punctured by leather needles.
Locate the top of the tear. Place the needle beneath the faux leather, with the sharp edge pointed toward the outside of the fabric. Insert the needle no more than 1/8-inch from the top and no more than 1/4-inch from the sides of the tear. Push the needle slowly, with steady and even pressure, until the knot catches on the inside of the fabric.
Pinch the sides of the tear together so the edges are flush. Insert the needle into the faux leather on the opposite side. As you push the needle through, align it so the curve allows you to pull the needle back through the other side of the tear. Continue inserting the needle on opposing sides until you have reached the bottom of the tear. Tie a small knot in the thread, and cut it as closely to the faux leather as possible.
Dampen a clean rag, and clean several inches around the tear. Allow the faux leather to dry completely before applying leather repair compound.
Turn on your iron, and wait for it to heat. Read the manufacturer's instructions on the denim patch to determine which heat setting to use. Cut the denim patch so it is approximately 1/4-inch larger than the tear on all sides.
Apply the denim patch to the tear according to the manufacturer's instructions. Allow the patch to cool for several minutes before proceeding.
Read the manufacturer's instructions on the leather repair compound. Put on rubber gloves to protect your hands, and then squirt a small amount of compound on top of the denim patch. Use a paintbrush to spread it in a thin, even layer. Allow the compound to dry for the amount of time specified by the manufacturer before applying another coat.