Measure the distance between the two pieces that attach to the wall from the center of one piece to the center of the next.
Transfer these measurements to the wall by making a dot to indicate the center of each piece. Check that both dots are level with each other.
Drill a hole into the dot on the wall with a bit just smaller than the molly bolt you will use. Repeat for the other dot.
Insert the anchor or molly bolt into the hole until the face of the bolt is flush with the wall. Repeat for the other side.
Line up a bracket on the wall so the screw hole lines up with the anchor or bolt.
Screw the bracket into place with a drill and a Phillips-head bit. Repeat for the other bracket.
Place the decorative arms over the bracket and tighten with the included Allen wrench.