Step 4: screws each side together
I started by screwing together the sides, the base and the lid. One thing worth noting is that Rough Sawn wood isn't always totally uniform which means you may have to space out the cross timbers slightly. Each side is the same simple construction:
3 or 4 long cross timbers and 3 upright supports.
I used the 32mm screws to put the sides together and the smaller screws to attach the casters.