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Carefully push all connected electrical wires and wire nuts up into the ceiling electrical box, ensuring no wires are pinched or exposed. Slide the chandelier canopy up along the chain until it sits flush against the ceiling. Take the decorative nut (often matching the chandelier's finish) and screw it onto the exposed threaded part of the main hanging bolt, just below the canopy. Hand-tighten this nut firmly to secure the canopy tightly against the ceiling, concealing all the electrical connections.