If your gazebo kit’s columns are not an integral part of the floor system, the next step is to bolt them to the base blocks. See the illustration below.
Then assemble the upper column bands at the top of the columns. Just finger-tighten the nuts until all of the upper column bands are placed. Tighten the nuts, alternating between the right and left nuts on each column. Screw the inside trim blocks in place with 3-inch trim screws.
Install the side panels by positioning each panel so it has equal margins on each side, and then attach each panel to the columns, typically with 2 1/2-inch screws.
Preassembled side panels are heavy and a bit awkward to maneuver, so be sure to have a helper on hand. You will also need a couple of tall stepladders.
Install the trim pieces, including the handrails. Set any exposed nail heads beneath the surface and fill the holes with matching wood filler. If you have stained or painted the structure’s pieces prior to assembly, touch them up.