Many people go into the hairdressers armed with inspiration snaps which usually show a perfectly polished celebrity on the red carpet... what they don't expect is to wake up looking like Fat B****** from Austin Powers.
Which coincidentally is exactly who one horrified admin assistant compared her new look to after a severe allergic reaction to hair dye caused her entire head to swell.
Kelly Kruppner got her naturally red hair professionally-dyed dark brown on 24 October for a change, after dying it years earlier without a problem.
But the 26-year-old woke up the following night to discover her face and head had ballooned, making her almost unrecognisable to her gobsmacked husband, Brandon Sprague, 24.
The hair stylist had applied a patch test for the dye behind Kelly's ear an hour before doing her hair - but had failed to leave enough time for the delayed allergic reaction to show up.
As the reaction progressed over the following days, Kelly says her scalp became covered in painful chemical burns that doctors say will take a month to heal, during which time she is now unable to use shampoo because of the severity of the burns.
She has now shared photos of her face during the reaction to warn others to leave their patch tests on for the recommended 48 hours to avoid the same fate she suffered.
Kelly, from Brockport, New York, US, said: "My husband woke up and I told him not to turn the light on because I looked so bad but he still turned the light on and he definitely got a shock. I scared him.
"It was really painful and each day it just got worse and more swollen. By Wednesday my eyes were almost completely swollen shut.
"My cheeks were really puffy so I thought I looked like Fat B****** from Goldmember, Austin Powers."
She went on: "I didn't even look like myself. It kind of looked like I was wearing a fat suit just for my face, it was awful.
"I kept saying I looked like Sloth from the Goonies and my friend sent me a picture of The Hunchback of Notre Dame, so there was a lot being thrown around about what I looked like."
Kelly says she has never suffered an allergic reaction to any beauty products before, so the horror swelling 12 hours after her appointment came as a big shock.
Emergency doctors told her it was the worst reaction they'd ever seen from hair dye and told her to stay off work for a week since her eyes were almost swollen shut, making it unsafe for her to drive.
Kelly said: "I went to the emergency room and they said it was going to take three to four weeks for the burns to fully heal - they said it ended up being a chemical burn instead of just an allergy.
"Three doctors total had to see me and come look at it, including a burns specialist, because they said they've never seen anything quite this bad with hair dye.
"My primary doctor gave me a steroid cream for the burns and a steroid pill to help but the ER doctor said it might not help because it's burns on an allergic reaction.
"For showering I have to take lukewarm or cold showers because my head is so badly burnt and I can't use shampoo right now because it could cause an infection or further swelling and pain."
Because of the severity of Kelly's reaction and scalp burns, doctors have warned her never to dye her hair again as she would likely suffer the same reaction, if not worse.
That means she will have to wait for the almost black permanent hair dye to grow out until she's back to her natural red locks.
Kelly said: "The burns are starting to scab over horribly and itch but my face is nowhere near as puffy, I'm starting to look like me again.
"I'll definitely never do it again and I would advise anyone to patch test regardless of what product they use just to be safe after having my experience."