No matter how much protective clothing that you wear when installing fiberglass insulation you can guarentee that you will be itching all over after working with fibergalss.

So before installing fiberglass insulation apply baby powder to your hands, arm, face etc. Then when you are cleaning up do not rub while washing. Instead use a hose and spray your arms with just the water. Do not rub with your hands.

Caution
If you decide to spray your face-plug your nose