Stand the bottom tray on a long side and the crosspieces on their ends. Lay one set of the cart's legs over these pieces, handle recess facing down. Line up the pilot holes with the insert nuts in the tray and crosspieces. Using a hex key, twist hex-head connector bolts through the holes and into the nuts. Fit one end of the handle into the recess, and use a 1½-inch stainless-steel screw to secure it to the leg through the countersink.