The process couldn't be easier: simply give control of your Instagram account to this shady, semi-anonymous website that literally has the word "creep" in its name, and it will automatically like an ancient photo from someone you follow, thus making them think you're a stalker who spent all night going through their selfies, inspirational quotes, and lunch photos. It's unclear whether the software is programmed to prioritize bathing suit shots, but it is our responsibility to assume that it does.
"Nana at the lake house last year. Miss u so much." Jackpot!
What do you get out of this? Absolutely nothing, beyond the satisfaction of attempting to make someone in your circle of friends or online acquaintances feel uncomfortable. On the upside, the real social media creepers of the world can now use "It wasn't me, it was a joke website!" as a valid excuse for the dreaded accidental late-night like, so keep that in mind.