A wooden tri-fold futon frame is one of the most basic designs for a convertible futon couch. Once assembled, you may use it for a bed platform or a seat. Unlike many other designs, a tri-fold frame folds your mattress along its length rather than its width. This makes twin and full-size folded tri-folds more like a chair than an actual couch. Regardless of the size, putting together and using a tri-fold futon frame is easy once you get used to it.
Lay the three sections of your tri-fold frame end to end, with the slats in the frame all aligned in the same direction.
Slide the forks of one section so they embrace the slats of the section next to it, positioning them so the mounting holes align. Do the same for the other joint in the frame.
Attach the frame sections. This step will vary according to your model, but usually involves either screws, nuts and bolts or wooden pegs.
Lay your futon mattress on top of the frame.
Remove the mattress. Once you get the hang of this process, you won't need to do this step, but while you're learning it will be much easier without the mattress.
Fold the frame at one of its two seams by lifting the frame sections on either side until they form an "A" shape with the fold between 30 and 45 degrees.
Lay the futon mattress on top of the folded frame, draping one end of the mattress over the fold.
Some models of tri-fold futon frames come with a "kickstand" to help them remain upright in couch position. During assembly, screw this piece in at the hole in one end panel. When converting to couch position, rotate the "kickstand" until it is firmly positioned against the floor. This will help the "A" portion of the couch not slip.