Skin types and concerns are important factors in coming up with a great minimalist skin care routine. Alster often tells her patients to "protect during the day and repair at night."

"Everyone should incorporate a daily cleanser, a topical antioxidant and a mineral sunscreen for protection during the day," says Alster. "At night, it's best to apply a retinol product to repair skin while one sleeps." Like The A Method C Antioxidant Gel 20%, $118, which helps prevent free radical damage.

Aharon suggests using a cleanser, moisturizer, sunscreen and lip balm with a few bonus things a couple of times a week. "I do still like to exfoliate once or twice per week, whether with a scrub or an acid. And normally incorporate a vitamin C serum into my routine."

Aharon points out that eye creams can be musts for some. But a general facial moisturizer isn't suitable for the eye area. She uses a light serum to prevent irritation and milia (tiny hardened pockets of sebum).

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Make sure the few products you're using are synergistic and that each one is targeting a different problem. That way you get the most bang for your buck.

Zilka says that all skin types benefit from a gentle glycolic acid cleanser, a niacinamide serum and a vitamin C moisturizer. Jenny Frankel, president and founder of Nudestix, likes using enzymatic exfoliants as well as acid as part of a regular routine. Although exfoliating every day may not be necessary. When it comes to moisturizers, look for ones rich in antioxidants and vitamin C, such as Nudestix's Nudeskin Citrus-C Mask & Daily Moisturizer, $38.

Cleansers are a must for everyone. Aharon recommends gel, cream or micellar water cleansers. Lighter formulas are generally better for oilier skin, while creams and balms are more suited to drier complexions. If you wash your face at night, it may not be necessary to give it a proper cleanse in the morning. Aharon says that a splash of water could be enough.

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A lot of brands have complete systems featuring products designed to work together. Thereby taking the guesswork out of coming up with a good routine. "When you use a routine from the same brand, it's a simpler routine," says Frankel. "When used together it actually elevates efficacy because it's been created specifically to work together."

We recommend Nudestix's Nudeskin 4-Step: Citrus Renew Set for Sensitive Skin, $82.

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Overly oily, dry, red or irritated skin may be signs your current routine isn't working explains Alster. Dullness, thick-feeling skin, larger-looking pores or pores filled with gunk are other signs your regimen isn't working points out Frankel.

"If you feel unhappy with your skin, then your routine isn't working," says Zilka. "You want to be using products that make you feel amazing — it's that simple."

You may also want to consider breaking up your routine. Use one serum in the morning and another in the evening. It's also important to allow enough time to see if a routine is working. Stick with it for at least a month before you judge.

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