As cliche as it sounds, I do actually have a bit more fun when I’m blonde. Last summer, I was feeling a bit blah about my look and decided to spice it up with a platinum hue. And boy was I hooked—I tried everything from girly rosé to icy, platinum blonde, until recently returning to my natural shade of brownish black.

Admittedly, the itch returned after researching for a story. I booked an appointment with Cassie Cohen, a colorist at Sharon Dorram Color at Sally Hershberger Salon right before my 10-year college reunion at Hampton University. The color was a hit with my former classmates and I was back on the blonde train.

During my color session, Cohen used Shu Uemura Color Luster Cool Blonde Conditioner ($58), which helped hydrate my strands post-bleach. “I love that it leaves your hair feeling hydrated and brass free, which is a hard combination to achieve,” she explains. “This product is great for both blondes and brunettes, and once rinsed clean, the hair is left without any funky color residue.”

Presumably, the one thing I had to switch up (other than my newfound confidence) was my wash day routine. Blonde shades notoriously start to turn dull, brassy or less than vibrant if your products aren’t up to par—to help, here’s a brief recap on what makes purple-based products stand out, plus, what to avoid when using them according to experts.

How purple shampoos work

It all goes back to art color theory class: Essentially, purple keeps unwanted undertones at bay since it neutralizes yellow. “There’s no magic or chemical reaction,” explains cosmetic chemist Stephen Alain Ko. “It’s the same principle behind mixing paint colors. Yellow and purple mixed together give you a more neutral, and earthy color, like brown or greyish-brown.”

And while you won’t actually adjust the color of your hair, you can adjust the tone and nix the brassiness. “Blonde hair, especially hair that has been chemically lifted to blonde, tends to have yellow undertones. When coloring the hair, hair colorists often refer to this as the DURP or dominating underlying remaining pigment. Adding a purple shampoo can neutralize some of the yellow undertone—turning it more silvery, grey, or brown,” he explains.

Except instead of mixing paints, you’re temporarily depositing colorants onto the outer-shaft of the hair which changes how the color of the hair appears. Consider your at-home tune-up to keep your new hue looking flawless for longer. “Purple shampoos are great for toning,” co-signs celebrity hairstylist and founder of Muze|Hair, Kiyah Wright, who works with Jennifer Hudson, Tyra Banks, and Laverne Cox. “I love using purple shampoo because it removes orangey brassiness that blonde hair tends to get over time.”

How to use purple shampoos

But, before you toss all your current products out, consider this: Purple shampoo and conditioner are great, but they’re an addition to your hair rotation, not your main squeeze. Really, they should only be incorporated once a week. For example, using these products too frequently can darken your blonde or potentially stain your hard-earned color.

“It’s often better to start slowly and build up intensity and adjust, instead of applying too much colorant. This can also help reduce the chances of an uneven application too,” explains Ko. “If there’s too much colorant deposited onto the hair, it can overpower the yellow undertones in the hair and turn the hair purple. The colorants found in purple shampoos and treatments are temporary though and will wash out over time.”

Especially in the winter, processed blonde hair needs extra nourishment. I can attest to this, I find myself conditioning my hair every few days versus once a week. Since I’m also natural, anything with sulfates makes my hair freak out, so I typically opt for gentle, cleansing conditioner options.

One tip I learned the hard way is A) Follow the directions, B) Rinse with cool or cold water, and C) Pick either a shampoo or conditioner (not necessarily both). In between my “purple sessions” I supplement with Joico Blonde Life Brightening Shampoo and Conditioner ($34), which gently cleanses while still maintaining my brightness.

“I wouldn’t recommend leaving a purple shampoo and/or conditioner in the hair no longer than five minutes,” adds Cohen. “Purple shampoo and conditioner is not in place of a gloss, just a tool to keep your color fresh in between color services.”

How to pick the right purple shampoo

Hairstylist and groomer, Jillian Halouska is a fan of OGX Hydrate & Color-Reviving + Lavender Luminescent Platinum Shampoo and Conditioner ($8 each). “This combo plus the penetrating oil helps retain the integrity of the hair by protecting the cuticle, while maintaining the tone,” she explains. “The blonde is kept from looking dull and lackluster by the special blends of lavender and chamomile oils and extracts in this sulfate-free hero shampoo.”

For clients like Shakira, Dascha Polanco, and Adrienne Bailon, celebrity stylist Cynthia Alvarez leans on Kevin Murphy Blonde.Angel.Wash ($32). “I love it because unlike some other purple washes, it won’t build up on your hair and dry it out,” she says. “It’s infused with natural goodies like lavender flower and mango seed butter. It also adds vibrancy to your hair and keeps the yellow away. I’ve tried so many different brands but I always end up coming back to this one.”

Those looking for a little extra strength should consider Keratin Complex Blondeshell Debrass & Brighten Shampoo — a top pick of celebrity hairstylist and creative director at Warren-Tricomi, Marc Mena, who works with Natalia Dyer, Madelaine Petsch, Chrissy Metz, Mindy Kaling, and more. “Not only is it gentle for blondes, but it neutralizes brassy tones in lighter shades of blondes,” he explains. It also fights fading and is infused with keratin to repair hair, plus add strength from potentially damaging color services.

Want a drugstore dupe? Too many stylists to count praised Clairol’s iconic shampoo, Shimmer Lights ($13)—including colorist, Cassondra Kaeding, who works with Rosie Huntington-Whiteley, Rooney Mara, Olivia Munn, Kate Hudson, and Ciara. “It’s an oldie but goodie! This shampoo helps brighten and refresh highlights in between services. I use this shampoo on not only my blondes but also my platinum and grey clients.”

With all of the praise, it’s still important to remember that purple-based products aren’t a magic bullet for blondes. It’s still hard to find any hard-evidence that they can alter your blonde completely, but that’s not to say they can’t assist with maintenance. “Anyone with light blonde hair or white and grey hair who is looking to neutralize yellow tones in the hair would probably benefit from a purple shampoo or treatment,” shares Ko.

Cohen suggests that colored shampoos and conditioners are to be used in conjunction with your normal shampoo and conditioning routine, not replace them entirely. “If you’re washing your hair three times a week, I would use the purple products every fourth wash,” she explains. “Overdoing the purple shampoo can leave color too drab.”

BTW, there’s a cool new plant called bakuchiol that has a purple hue if you’re into the color extending into your skin care. It’s an Ayurvedic replacement for retinol, if you can’t take the potency of vitamin A.