So what if you skimp a little on sunscreen, right?

That’s exactly what Valerie Carvajal wrongly believed all of her life.

Scary as it sounds, women like Carvajal are not an anomaly.

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Last year, SELF ran a story that detailed one woman’s skin-cancer scare.

All were diagnosed with skin cancer before age 30.

They learned their lesson the hard way.

Let them prevent you from making their mistakes.

In college, I was a lifeguard.

I rubbed on sunscreen in the morning but rarely reapplied later in the day.

But I thought I had at least 50 years before I’d have to worry.

I had skin cancer.

Getting rid of itA doctor took off the remnants of the bump.

I began returning to the dermatologist twice a year for a skin check.

But new cancers kept appearing.

Actinic keratoses (AKs), which are precancerous cells, grew on the tip of my nose.

The aftermathSkin cancer will be a lifelong battle for me.

One year following the Efudex treatment, my doctor found additional AKs in the same area.

I’ll always have scars and a deep groove in my right nostril.

The hardest adjustment, though, has been losing the freedom of the outdoors.

But the changes are worth it to stay safe.

(Chemical sunscreen ingredientsanything other than zinc or titanium dioxidetake that long to activate.)

Coat skin that will be covered with clothing, too.

A white cotton tee only has an SPF of about 7; the bare skin under it can burn.

But two years later, tanning became my drug of choice.

I went four times a weekI never thought I looked dark enough.

I scheduled my first-ever skin check with Beth Diamond, M.D., of Annapolis.

Naive about my risk, I went tanning the week of my appointment.

But within minutes of seeing the mole, Dr. Diamond told me her suspicion: melanoma.

The excision indicated stage IB, a deep lesion that hadn’t metastasized.

Luckily, that meant surgery only; no chemo.

I went home immediately following the surgery, but my recovery was excruciating.

I couldn’t get out of bed for two weeks because it hurt to move my back even slightly.

Of those, only three were actually normal; the 17 others were atypicalnot cancerous but suspicious.

I use sunblock with an SPF of 30 every day, and I will never tan again.

Base tans are dangerous, as they provide a sense of false security.

I never sunbathed, and I always wore sunscreen when I knew I’d be spending time outdoors.

It looked like a pimple and became red and irritated when I picked at it.

The biopsy, however, confirmed his gut diagnosis.

Getting rid of itBack in New York, I made an appointment to remove the lesion.

But rather than one surgery, it requires several in one day.

It took three tries to remove my diseased skin, the size of a nickel.

I’ve had two moles biopsied and one of them removed since my surgery.

Skin checks are now routine for me; I go every six months.

Cooley has fair skin.

Be on the lookout for pearly-looking pimples that overstay their welcome.

If they’re not gone in a week, see your derm.

And choose your protection wisely.

Dr. Webb also advocates wearing a hat outdoors.

Photo Credit: Scogin Mayo