This is a beautiful, sturdy bookcase that really compliments industrial or farmhouse decor. It is tall and heavy — 100 pounds — and the assembly directions recommend 2 people to put it together.  I live alone. Here’s how I built it. I followed the directions on assembling the uprights and attached the cross bars (step 1 & 2)    - only hand-tighten all the screws/bolts at this point.  Step 3 says to fasten the shelves from the top down with the unit laying on the floor, but how do you stand the completed unit without help?  Instead I installed the bottom two shelves and then stood up the unit near where I wanted it. The bottom two shelves kept the unit square as I installed the top piece and the other three shelves.  All the screw holes lined up perfectly. Then tighten all the screws/bolts. Easy!