These futon frame instructions are designed to help assemble a variety of different frames and may therefore not list the exact parts you have or look exactly like the frame you are trying to assemble.
Metal and wood futon assembly instructions are offered here for free for anyone who might need specific futon or furniture directions. In the mean time, you might check one of the instruction booklets found here. Often, futon companies are very similar in the way they construct their futons. Although futon quality will vary from one manufacturer to the next, these futon and other furniture instruction booklets should give you a good starting point.
Assembly Instructions for Three Basic Futon Frame Types (click your frame type below)