I’m a natural blonde and have naturally blonde (read: invisible) eyebrows to match — which would be fine, except I love big, bold, dark brows. So I put a lot of time, effort and beauty products into creating the illusion that I have big, bold, dark brows: I tint my brows, fill them in, shape them meticulously, and brush them into their biggest, boldest iterations. If I don’t have my brows “done,” I feel naked.

Other women who have a similarly complex, non-negotiable eyebrow grooming routine know that keeping your brows looking fly becomes much harder in the summer, when you’re perpetually drenched in sweat. Have you ever gone to wipe off your forehead and smeared your eyebrow across your temple? Yeah, not cute.

Luckily there are ways to keep your eyebrows up to your exacting standards even in the face of a massive heat wave and overactive sweat glands. Here are 3 secrets, learned from many trials and errors, for truly sweat-proof brows that last all day:

Step 1: Use a waterproof eyeliner pencil to draw them in.

Brow pencils are great, but they don’t hold up well to sweat and humidity. Waterproof eyeliner pencils are made to stay on all day, even through weepy weddings, so I’ve found they’re a better choice for filling in/drawing on brows in hot weather.

MORE: 21 Gorgeous Celebs Without Makeup On Instagram

I’m a fan of Urban Decay’s 24/7 Glide-On Pencil in “Whiskey,” a rich chocolate brown. I use it to fill in sparse spots and define my brows, and it creates a perfect waterproof base for the rest of my brow routine.