Flirt in a safe place. Don't flirt on the edge of a cliff, on a ladder, on a volcano, near a tub of needles, etc. If you get nervous and faint, you won't faint to your doom.
Flirt with people who aren't going to harm you. Don't flirt with an axe murderer, a sociopath, a clown with rabies, etc. Flirting the wrong way with any of these beings could result in serious harm.
Flirt with humans. Animals, plants, fungi, rocks and microbes don't really get flirting, and some of them can hurt you if you touch them. Some examples of things you shouldn't flirt with are diamonds, corpse flowers, tardigrades, etc.
