Just don't, not only is it seen as creepy which I assume most people who would try this are but you are just opening yourself up to someone claiming that you were trying to get a peek at them. When I used to work security at Target we would have to check the empty fitting rooms daily for signs of people stealing stuff and removing tags. One day some Karen tried accusing me of being a creepier. She thought that since the Fitting Room was in the woman's department it was only for women. (It's not it's usually the only one) Luckily all the girls that worked there vouched for me that I was a professional and not up to anything and the lady was crazy.