Flip the couch over to access the underside. Cut away any fabric that covers the bottom using a utility knife.
Inspect the frame and determine how it is assembled. Some are nailed or screwed together and some frames are bolted together.
Remove any bolts you can see using a socket wrench set. If the frame is screwed together, use an electric drill with a driver bit installed to back out the screws. Some couches may use screws and bolts. The goal is to remove all the screws and bolts you can locate.
Pry apart the frame after the bolts and screws have been removed, or if the frame is nailed or stapled together. Use a flat pry bar and a hammer. Pry apart locations where pieces of the frame are connected, such as the back to the bottom or the sides to the center frame. As the frame becomes disconnected, cut away the fabric from the areas it is attached to the frame using a utility knife.
Break apart the back and sides from the bottom as you disassemble the frame. The pieces will become easier to remove as the frame is disconnected.