Seating was very easy to assemble. It took awhile because of how many pieces there are, but it was straightforward and I had no issues. As for usefulness, this is not a very comfortable set. The seat cushions attach to the seats but the back cushions are awful and do not stay up. The cushions are pretty thin and extremely lightweight, too, so I have to put them all in the shed if the wind picks up. However they do dry quickly after a rain, so that is a big plus.