The legs are assembled with 2x2x22.5″ as the sides and 2x2x17.5″ on the top and bottom. Leave 4″ on the bottom for the shelf to attach and for floor clearance.
Once the legs are together its time to get them installed to the top. Turn the top with top facing up. Place the legs on the top with the additional 2x2x17.5″ boards. Use 2-1/4″ screws to connect the legs to the top.