Rinse off with cold water before the hot shower.
"A Tip?
Hahaha, yeah.
Anybody that is dealing with taking out old insulation, when you get home and finish work at the end of the day and you go to wash that off of you, start with cold water.
A lot of people know this, but also a lot of people don't.
One of the guys on our crew lapsed his mind and forgot to wash off with cold water and got right into a hot shower and set all that fiberglass right into his pores and was paying for it the next day.
If you wash it off with cold water, your pores close and the insulation rinses right off of your skin and you won't itch for the rest of the night."
—Ben Bogie, Built to Last Design and Build, from the jobsite of Professional Remodeler's 2017 Model Remodel
WASH WITH COLD WATER FIRST WHEN YOU'VE BEEN HANDLING OLD INSULATION!
(ask me how I know this...)