As mentioned in numerous reviews, the styrofoam packing falling apart is a joke.  The seller needs to address this with the manufacturer.   Tip...best way to clean up...use a shop vac.

I can't imagine using that little wrench it came with to assemble.  I used a phillips screwdriver and a socket wrench.  Not an easy assembly for one person unless you lay it on its side, and only attach one set of vertical supports and rings at a time.  The rings don't always sit flush with the poles, but once tightened, they are fine.

I dug a hole and placed the trellis in, then a clematis, and then backfilled.  First ring is probably 3" about ground level.