LEIGH CAMPBELL: 'At 42, here are 3 product switches I wish I made earlier.'

You live and you learn, so the saying goes.

I've been on the planet for 43 years next month, and almost half of those have been spent trying, talking and writing about beauty products.

You'd think I would have had my ride-or-die routine sorted somewhere back in my Cosmopolitan Magazine days, but things change.

Formulas. Trends. Ingredients. My skin. 

Watch: When it comes to skincare, it's never too late to learn. Here's makeup artist Amanda Ramsay with her top tips. Post continues below.

I read an excellent article this week by You Beauty Collective writer, Teresa McNamara, in which she explained that at the age of 54, she had a lightbulb moment when she started paying more attention to what she puts on her skin, taking the time to learn how different ingredients work. 

Have you seen Teresa's skin? It's proof she's a grade-A student.

I love that women are taking the time to educate themselves about the 'how' and 'why' when it comes to their routines.

While the world of skincare can certainly be overwhelming, there are more accessible and easy-to-understand explanations available to everyone, now more than ever. Thanks, internet. (And a pretty fabulous podcast called You Beauty)

I had a head start over the average person thanks to my job, but I'm still a regular woman learning what works for me and also learning what fears or false beliefs I need to let go of. 

1. Oil isn't the enemy.

I used to dream of having a dry skin type so I could lather on layers of delicious hydrating skincare. I avoided face oils for years (even though I longed to use one when I read celebrity routine articles in magazines and lusted over their glow) because I thought it would make me break out or add extra shine to my greasy parts.  

The day I ditched that belief and added a face oil to my routine was the day my skin changed. Despite having an oily forehead, nose and chin (and some pesky breakouts), the right oil for my complexion helped balance out sebum production and even soothed my spots. 

My favourite oils for my skin type are jojoba oil, squalane and argan oil. They balance and plump. Perfect.

 2. Squeaky clean is not a good thing.

We use a face wash to clean our skin, obviously. 

And thanks to the aforementioned oil issue, I used to use rich foaming cleansers that would take all that away, leaving my skin so clean (read: striped) it would literally squeak when I ran my finger over it. 

I also went through a phase of using an electric cleansing brush that would manually rotate, scrubbing away the day. And yes, I used it every day — it was the trend back then.

My poor skin barrier! These habits meant my skin was clean, but my acid mantle (the protective layer of my skin) was destroyed, leaving my skin striped and reactive. It also produced more oil in an effort to restore itself, creating a cycle. 

When I discovered micellar water (Bioderma Sensibio H2O was the first and is still the best if you ask me) and switched to gentler forms of face wash I could almost hear my skin sigh with relief. 

Removing makeup and debris is important, but so is protecting the skin barrier. It's what makes our skin strong, smooth and glowy.  

3. Sunscreen is a gift.

You knew this one was coming, right? 

Despite being in the industry for ages, back in my late 20s and early 30s I struggled to find the right SPF formula that didn't make my skin greasy, give me pimples, or make my makeup look awful.

Thankfully, sunscreen ingredients and textures have improved exponentially in the past decade, meaning there's a formula that will work for you no matter what your skin concerns are. Now there's no excuse not to wear sunscreen every single day as the last step of your skincare routine. 

If you need more convincing, consider this. Around 90 per cent of visible changes to the skin occur due to UV radiation. NINETY PER CENT! And that doesn't mean sunbaking or getting a tan on purpose — UV exposure happens gradually and incidentally when we're just living our lives. 

 There is absolutely no point spending money on skincare or facials if you don't wear SPF because sunscreen is the number one most effective anti-ageing step that exists. It's a fact.

Want to take a peek at Teresa's glorious skin and learn about the five products she uses to get it so glowy? Click here.

Feature: Supplied.