Installing insulation around junction boxes that house electrical receptacles and switches, and around wiring in walls and ceilings requires some special techniques. Fortunately, all of the special techniques are very simple and do not require any special skill or equipment.
When cutting insulation around wiring, be sure to keep your utility knife clear of the wires.
Watch the videos for handy demonstrations and you will be sure to do a professional job.
Junction Boxes - Hold the insulation up in the wall cavity and check where the junction box lines up. Cut a notch in the batt for the junction box. Place that cutout of insulation behind the junction box, and then insert the rest of the batt in the cavity.
Wiring in Walls - When electrical wiring passes through a stud cavity, split the insulation with a utility knife and fit half in front of and half behind the wire so that the wire is nested inside the insulation. If the wiring is located close to the inside surface, then press insulation behind the wiring.
Wiring in Ceilings - Insulation should be placed between electrical wiring and the ceiling.