At 123 lbs this is no lightweight, cheap piece of furniture.
I opened the top of the box, then tore down all 4 corners, so that when it dropped the cardboard would protect the futon from the floor while I put it together. It turns out the instructions recommend this.
When I opened it, I was surprised to find only 4 things in the box. The instruction booklet, 2 front bars and the futon. The futon is hinged in the middle, so the underside of the left and right half are against each other.
I read thru the instructions and found that they're about the best I've ever seen.
I learned you should have 2 people for assembly and that it would take about an hour. I had no help and because of a frustrating, but easily fixed problem, it took me 3 days.
On the Parts page it shows all the parts, each assigned a letter, its name, the quantity of parts and a box to check as you found each part before assembly.
At the bottom of the Parts page it shows the underside of the futon with a 3-sided line and says: 'Some parts will be found in the compartment under the seat as shown.'
I opened the 2 halves of the futon as it was standing on what would be the back of a couch. There was a 3-sided zippered compartment under each half of the seat. Opening the 2 compartments, I found all the rest of the parts including the 2 arms. When I removed one arm, behind it I found the Hardware Pack with all the nuts, bolts, washers and tools needed. Everything was sealed in plastic. The hardware was all grouped together by type and had a number next to it that matched the item on the Hardware Pack page, along with the size and quantity of items.
On the Hardware page it tells you not to tighten the hardware until the entire assembly is complete.
Each part of the assembly is shown as a separate 'Step' listing what parts (by letter) and what hardware (by number) are needed for that step as well as showing a drawing of how to do it.
On Step 2 you screw the short end of 4 double bolts into holes in the arms. The bolts have a short threaded section, a short unthreaded section, then a long threaded section that will fasten the arm to the futon.
On Step 5 you insert the 4 bolts from the Arm into holes in the material and thru the frame into the underside compartment. You then add a washer, spring washer (lock washer) and nut then tighten the nut with the wrench. They warn against using power tools, so you don't strip the threads.
WARNING: Be sure to read the next section to avoid my mistakes.
It's hard lining up the bolts with the holes because there's no a lot of light between the futon and arm. I spent 2 days trying to get the right arm on, but the bottom bolt wouldn't go thru. On the third day, I removed the bottom bolt and the Arm went on. I removed the Arm and pushed the bolt thru each hole from the compartment. The bolt wouldn't go thru the bottom hole. The hole in the material was 1/4 inch off. While holding the bolt in place, I cut the material over the bolt with a jackknife and then it went thru.
I put the bolt back in the Arm and the Arm went right on.
The next part of Step 5 is to put a washer, spring washer and nut on each of the 4 bolts in the underside compartment. With the spring washer on, there wasn't enough bolt to get the nut on.
The third bolt is about the center of the Arm, so I used only the washer and the nut on that one. When tightened, it pulled the Arm tight to the futon, so there was enough bolt to put both washers and nut on the other 3 bolts. With those tightened down, I removed the first nut, add the spring washer and tightened the nut. Then I repeated the process with the left arm. Oops!
I then had to loosen all 8 nuts to do Step 6 - fasten the left and right bar to inside front corner of each Arm.
After attaching all 6 legs, I had to get a neighbor to help lift the futon and set it on its legs. I could have done it myself, but was afraid all the weight at an angle on the back legs might snap them off as I tried to set it up.
The helpful Hints page could have used a little extra text. The page uses pictures to show how to convert it from a couch to a bed and back. The picture shows 2 legs folding out the back of the couch to support it when its laid down.
I felt all over the back and couldn't find anything. I finally leaned over the back and finally found a zipper. Each side of the back has a zipper pocket that the leg pivots down out of.
I sat and then lay on the futon and its firm but comfortable. I've seen some that you could feel the frame thru the cushion. NOT this one.
I'm tall and I still had futon left over when I lay on it. I grabbed a pillow and slept comfortably on it that first night.