As an aesthetician, I spend a lot of time correcting skin mishaps, from the unexpected side effects of harsh products to post-laser scarring (which typically only occurs if you really mess up your SPF). I’ve also made plenty of mistakes myself, since it can be pretty tempting to act as my own personal guinea pig. I’ve rounded up the most common slip-ups below—the good news is that they’re super easy to avoid once you know about them.

1. Overusing Exfoliants

This is what happens when you go too hard on your exfoliants: As you’re exfoliating away, a vital component of your skin, called the lipid barrier, starts to dissolve. When too much has been removed, your skin’s barrier becomes compromised. There are a host of symptoms you can experience if you’ve overdone it with acids or scrubs: Best-case scenario, your skin becomes dry and dehydrated; worst case, your skin becomes exceptionally sensitive, burning, and irritated.

Accidentally overprocessing your skin from time to time isn’t too big of an issue. Your skin may be uncomfortable for a bit, but if you let it heal, then you’re back to business as usual. The major concern comes when we’re dealing with chronic symptoms from doing too much. Whether you experience persistent dry skin, dehydration, inflammation, or irritation, all of these issues can lead to premature aging over time (which I’m pretty confident we’re all trying to avoid).

This doesn’t mean you should avoid using chemical or physical exfoliants in your routine. They can be essential in maintaining glow. You could have the perfect product but need to use it less frequently. Or maybe what you’re using is actually too potent for what your skin can tolerate. It’s sort of like a choose-your-own-adventure for your skin’s unique disposition. One good rule of thumb is to start at a lower concentration and work your way up.

2. Skipping Sunscreen (Even in Winter)

I hate to be the bearer of bad news but… it ain’t all about what your momma gave ya. Regardless of how good you think your genes are, using a good sunscreen can make or break how you age. Actually, it’s not even a case of if it can make a difference—it will.

There are two types of sun rays we need to protect our skin from: UVA and UVB rays. To defend our complexion from unwanted photodamage, we need to wear a broad spectrum sunscreen every day. Yep, even when it’s cloudy. No exceptions! Driving during your commute, sitting next to a window while reading, or simply going for a walk with your dog are ample opportunities for those rays to damage your DNA. Finding an SPF you can enjoy using as part of your daily regimen is key to conserving your beautiful skin in the long run.

Remember this viral photo of a truck driver?

The right side (his left) was exposed to the sun during cross-country treks—you can see the effects of long-term sun damage for yourself.

3. Thinking DIY Treatments Are Always Your Friend

People still try DIY treatments with crushed aspirin, baking soda, and lemon juice thanks to everyone’s favorite social vision board—Pinterest. But some things just aren’t meant to be used on your skin! While you can create a honey and yogurt mask to nourish your skin and gently exfoliate (it’s quite tame and feels lovely), aspirin, baking soda, and lemon juice all have the potential to wreak havoc on your skin’s barrier.

Over the years, I’ve received frantic emails from people asking how to repair stinging, hot, angry skin after rubbing a lemon on their face. The goal is to brighten their skin, and instead, extremely acidic lemon juice leaves them with a red, sensitive mess. The recovery time can take weeks! The best thing to do is go back to the basics: Cleanse, moisturize, sunscreen, and nothing else until your skin is back to normal. And the next time you see a skin care recipe that piques your interest, practice due diligence and research it first.

4. Thinking You Need to “Feel It Work”

Perhaps the most overlooked mistake is not being kind to your skin. Generally, we tend to do too much or are too aggressive. The idea you need to “feel it work” for products and treatments to transform your skin is incredibly false. The truth is, in most cases, you don’t want to feel anything—or, at the very least, it should be minimal. A tingling or stinging sensation is your skin telling you something isn’t quite right, and you really should listen.

Even if you don’t have sensitive skin, treating your skin gently is key to preventing premature aging. Of course, there are skin types that can tolerate aggressive treatments, but that doesn’t mean your skin needs them. Pay attention to products or treatments that cause discomfort and dryness, evaluate what’s causing your skin to behave that way, and reconsider how often that part of your beauty regimen is practiced (and maybe eliminate it completely).

Be good to your face, treat it carefully, and you can have skin you’re proud of at any age.

Sarah Payne is a licensed aesthetician and beauty and wellness writer devoted to helping women feel beautiful and confident in their skin at any age. Sign up for free skin and wellness tips on her site.