If you're hunting for a Halloween costume that's instantly recognizable, easy to DIY, and all over everyone's feed right now — Sydney Sweeney just handed it to you. In mid-October, she posted a full Halloween costume idea through her brand SYRN: her own take on Cassie Howard's puppy-inspired look from Euphoria Season 3. Searches for "Sydney Sweeney Halloween costume" exploded overnight.
The best part? You don't need her $269 corset to pull it off. Here's how to DIY the viral look, plus four more of her most iconic outfits that make killer costumes.
The viral look: Cassie Howard's puppy costume (Euphoria S3)
This is the one breaking the internet. Sydney recreated Cassie's Season 3 Halloween look: a chocolate-brown satin corset, brown boy shorts, a plush headband with floppy puppy ears, a leather collar with a leash, wide leather cuffs, and slouchy brown suede boots. The makeup is what sells it — a small heart drawn on the nose, faux freckles across the cheeks, pink blush, and brown-outlined lips.
DIY it for under $50
| Piece | Budget swap |
|---|---|
| Brown satin corset | Any brown corset top or lace-up bustier from a fast-fashion store |
| Brown boy shorts | Brown bike shorts you already own |
| Puppy ear headband | Brown plush headband — glue on floppy ears cut from felt |
| Leather collar + leash | A brown belt worn as a collar, plus a cheap pet leash |
| Leather cuffs | Brown wristbands or cut the tops off old boots |
| Slouchy brown boots | Any brown boots; scrunch the tops down |
The makeup (the most important part)
- Base: Your everyday foundation, a touch warmer than usual
- Freckles: Dot a brown eyeliner pencil across your nose and cheeks, then tap lightly with a finger to soften
- Heart nose: Draw a tiny heart on the tip of your nose with brown or dark pink liner
- Blush: Heavy pink blush on the apples of your cheeks — Cassie goes bold
- Lips: Brown liner to outline, pink gloss in the center
- Hair: Loose honey-blonde waves with a side part (a wig works perfectly)
4 more Sydney Sweeney looks that make great costumes
1. Anyone But You — beach rom-com Bea
Her most wearable costume. A breezy summer dress or a bikini top with a sheer cover-up, tousled beach waves, and minimal makeup. Add a fake boarding pass or a "Sydney to Australia" sign as a prop and everyone's in on the joke. Comfortable enough to actually enjoy the party.
2. Madame Web — Julia Carpenter
For the comic-book fans. Julia Carpenter's look is a dark, sleek bodysuit-style outfit with a spiderweb motif. A black long-sleeve top and leggings with a web pattern drawn on in fabric paint gets you 90% there. Bonus: it's warm enough for a cold October night.
3. Immaculate — horror nun
Her 2024 horror film gave us one of the eeriest simple costumes of the year. A black habit-style head covering (a black scarf draped right does the job), a long black dress, a cross necklace, and pale, unsettling makeup. Simple, cheap, and genuinely creepy — perfect if you want scary over sexy.
4. The jeans ad look
Her viral jeans campaign became one of the most talked-about pop culture moments of the year. The costume is almost comically easy: great-fitting jeans, a simple white top, and confident energy. It's a costume and a conversation starter — everyone will know exactly who you are.
Couple & group ideas
- Cassie + Maddy: Pair the puppy look with a friend doing Maddy Perez (dark blue eyeshadow, black mini dress) for the ultimate Euphoria duo
- Bea + Ben: The Anyone But You couple — one in beachy Bea, one in a rumpled button-down as Ben
- Spider-Women: Group up as Julia Carpenter with friends as other spider-heroines
Last-minute version (under 1 hour)
No time to shop? The puppy look compresses beautifully: brown top + brown shorts + ears headband (any animal ears work in a pinch) + freckles and a heart drawn on your nose. The makeup alone reads as "Cassie" to anyone who's seen the posts. For more closet-friendly ideas, check our last-minute Halloween costumes.
How we choose
We build costume guides from what's actually trending — this one started because Sydney posted the look herself and searches spiked 600% in a week. Every DIY swap here is picked to be genuinely findable (your closet, a craft store, or fast fashion), not a fantasy shopping list. No sponsored placements, no paid rankings.
