Bend twisted end of each wire into clockwise loop, and place each loop under terminal screw on socket with loop curled clockwise around screw. Tighten terminal screws. As each screw is tightened, clockwise loop will pull wire tighter under screw head. (A counterclockwise loop would tend to loosen wire.)
Clip off excess bare wire with diagonal cutters. All uninsulated wire must be under screw heads, with no loose strands or exposed bare wire. If bare wire is visible beyond screw heads, unscrew terminals, remove wires, and make connection again.