It’s tough to resist squeezing a juicy pimple. You probably want to get rid of it quickly and may feel like you know exactly how to do it after having watched hundreds of pimple-popping videos online.

Few things are more tempting than picking at a new zit that’s just appeared. After all, it’s pretty gratifying to see the built-up gunk release from your pores—plus, they always seem to crop up at the ...