Skincare is a part of your overall health, so it’s definitely worth shelling out some extra cash for, especially if you’re purchasing a serum as they deliver the most highly concentrated active ingredients and are considered the treatment step in your routine. This means that you’re going to get much more out of serums than a cleanser or moisturizer, and you’ll notice that fact reflected in the price.

So, if you’re spending a considerable amount of money on a small bottle of serum, you’re going to want to make sure that you’re using it carefully and not unnecessarily wasting the precious stuff. These are some of the most common serum-wasting mistakes and how to avoid them, according to Gina Mari, celebrity esthetician.

Forgetting to exfoliate

Exfoliating is an essential step to get rid of dead skin cells on the surface of your skin. It brightens your complexion and makes it easier for serums to penetrate the skin. According to Mari, “exfoliating the skin prior will allow for deeper product penetration.” You don’t have to exfoliate every day though. Twice or three times a week should do the trick.

Applying in the wrong order

The best order of application is to cleanse, then exfoliate (if you need to), then apply toner, then a serum. This will make sure that your skin is properly prepped and your serum can get deep into your pores. To finish it off, wait five to 10 minutes to allow the serum to seep into your skin, then seal the deal with a moisturizer.

Rubbing instead of patting

Rubbing in the serum with your fingers will result in much of the serum getting into your hands instead of your face. To avoid this from happening, “always apply in an upward motion and avoid rubbing and tugging the skin,” Mari says. Plus, the pressing motion will help the product really penetrate into your skin, so you’ll get more results with less product.

Mixing ingredients

With serums, less variety is more. If you use different serums at once, then you might end up combining ingredients that might cancel each other out or cause irritation, such as retinol and vitamin C. Instead, Mari suggests that you “pick one and allow it to do its job.” If you want to get a variety of benefits from your serum, Mari assures us that “there are many serums on the market that have the perfect blend of actives, therefore leaving the guesswork out of the equation.”