At a Halloween party, the makeup that makes everyone gasp is usually not the kind you can see in daylight — it is the kind that glows in the dark

The moment the lights go down and the blacklight (UV light) comes on, the stars, skeletons and spider webs on some people's faces suddenly light up, like fluorescent paint that appeared out of thin air. The secret behind that effect is a little box of glow paint pens

But there is one all-important precondition: it has to be skin-safe. No matter how pretty they look, highlighters, markers and ordinary colored pens should never go anywhere near a kid's face. Below we explain from the start how to choose them, how to use them and how to make them really glow

What glow paint pens are

First, let us be clear about what trick it is playing

A glow paint pen is a pen you can use to draw designs on skin — what sets it apart from ordinary face paint pens is that the pigment inside is fluorescent. In normal light it may look like just a faint wash of color, but the moment the blacklight (UV light) comes on at the party, the places you painted light up in a flash and give off fluorescent color

So the right way to use it is: paint first, then turn off the lights and switch on the blacklight. In a dark room you can see at a glance what everyone has painted on their face — which adds a layer of party surprise that ordinary makeup does not have

Why it has to be skin-safe

That one rule is the heart of everything in this article

Skin is something that comes into direct contact, so anything you paint on a face or an arm has only one precondition: buy skin-safe products. Specifically:

Only pens clearly labeled skin-safe, non-toxic and washable may go on skin

Ordinary markers, whiteboard pens, highlighters and permanent markers — these are made for paper and plastic, and the dyes inside are not designed for skin and may contain irritants, so they must never be drawn on skin, let alone used on little kids

Looking for these words matters far more than looking for a brand: skin-safe, non-toxic, water-based and washable

How to choose: six key points

When picking glow paint pens, check these points:

Check the packaging label. This is the first gate. Anything without a skin-safe, non-toxic or washable label is out, no matter how cheap or how pretty it is

Go for the liquid paint type first. Liquid or pen style paint pens are smoother and easier to draw lines with than crayon types, and their lines are finer, so they handle detail better. Crayon types are good for coloring large areas, but they struggle with fine lines

Avoid irritating ingredients. If the formula contains too much artificial fragrance or alcohol, it may irritate skin. Choose ones with a simple formula that are labeled gentle

Make sure it washes off easily. A good skin-safe pen comes off with warm water and soap. If you draw something and it will not wash off no matter how long you scrub, then it is not meant for skin, so avoid it

Test the glow first. Don't rush to put it on your face right after buying it —— draw a few strokes on the inside of your arm and shine a black light on it to see whether it really glows and whether it's bright enough. Some pens claim to be fluorescent but look dim under a black light, so inspect before you buy

Kids' versions are more reassuring. When picking for your kids, choose pens specifically labeled suitable for kids and safe for kids' skin, for a better guarantee of gentleness

How to use them: from patch testing to painting

Once you've chosen the right ones, there are a few steps you can't skip when using them:

Start with a small patch test on the skin. Draw a small stroke on the inside of your wrist or behind your ear, wait about ten minutes and check for redness or itching. If there's no reaction, then go on the face —— especially for kids with sensitive skin, this step is not optional

Use it on clean, dry skin. Wash your face and dry it first, then paint. Where there's lots of sweat or oil, the color smears

Draw your lines along the tip of the pen. For fine lines and patterns, keep the tip lightly against the skin and follow the outline stroke by stroke. For a deeper, brighter color, go over the same spot once or twice more

Pair it with a black light. Fluorescent pens only glow under UV light. Have a black light ready at the party so your makeup can really light up —— this is the key step in the whole routine

How to make the glow shine

To make glow makeup look its most stunning in the dark, here are a few tricks:

You absolutely need a UV black light. Without a black light, a fluorescent pen is just an ordinary pen. Use the one at the venue if there is one; if you're hosting, get a small one

A light base makes it brighter. If the pen color isn't bold enough, lay down a base with a white or light skin-safe paint pen first, then draw the fluorescent color —— a light base makes the glow brighter

Put it in a dark corner. The darker the place, the more obvious a black light's effect. Put the black light in a corner or off to the side of the party, and the glow pops out the moment someone walks past

Don't paint too densely. The beauty of glow makeup lies in accents —— a few stars, one spider web, that's enough. Filling the whole face just turns into a blur you can't make out

Safety and removal: four things you can't skip

Even with skin-safe pens, don't forget these safety basics:

Only use skin-safe pens. This one bears repeating because it really matters —— anything that isn't skin-safe must never touch your skin

Don't paint around your eyes or on your lips. Eyelids, the area near the lash line and the lips are the most sensitive, so avoid them. Stick to safe zones like cheeks, forehead, arms and chin

Don't paint over wounds. Skip any spot with a cut, wound or rash

Adult supervision for kids. Little ones drawing on their own can easily get it in their eyes or rub it into their mouths. Keep an eye on them, and once it's done remind them not to lick the pen marks on their face

Removal: warm water plus soap or cleansing oil. Wet the area with warm water and gently massage with soap or cleansing oil and the paint comes off. Don't scrub hard or wipe roughly with alcohol, since that damages the skin. Follow with a pass of facial cleanser and you're completely clean

A few look ideas

Fluorescent paint pens can draw more than you'd imagine:

Stars on the face. Dot a few little stars on the cheeks and under a black light they look like they glow in the night, simple and pretty

Spider web on the forehead. Draw a few arcs from the middle of the brow out to both sides, then link a few horizontal lines and you have a spider web. Painted on the forehead it stays out of the way and feels so Halloween

Skeleton lines. Draw a few white or glow-in-the-dark skeleton bone lines on the cheeks or chin, add black eyeshadow, and a glowing skeleton comes to life

Glowing wound. To match the fake blood from earlier, draw a glow-in-the-dark wound line on the face and under a black light it looks like a glowing scar——cool and a little creepy, a real head-turner at a party

Add a glow bracelet. If you would rather not paint your face, draw a ring of glow-in-the-dark stars or a name on the wrist, pair it with a black light and it still stands out

One last thing

Glow paint pens are one of the best-value surprises at a Halloween party——a few pens are all it takes for kids to become the one who glows in the dark

But the one thing every good look depends on is the word safe. Look for skin-safe, non-toxic, washable formulas, do a patch test first, avoid sensitive areas and have an adult keep an eye out——only then can glow makeup be the fun of the night instead of a hassle

Next party, when the lights go down and the black light comes on, the stars on your kid's face light up in a flash——in that moment you will not just smile, you will feel the peace of mind of knowing you picked the right thing