1. Slather on sunscreen
Like your skin, your hair needs protection from UV rays—or you risk suffering "oxidation," a process in which your hair turns a funky hue (typically  something in the not-found-in-nature orange family). To prevent this, Hazan swears by Phyto Plage L’Original Beach Spray ($22; ulta.com), a light oil that deflects the sun’s rays before they can mess with your haircolor. Spritz it on daily, then style as usual.

2. Hate hats? Don a mask instead
Coating your hair in a deep-conditioning mask protects your hair nearly as well as a hat—and you’ll have the added benefit of giving dry tresses a moisture boost. Bonus: The heat of the sun ensures greater, faster penetration of the conditioner’s hydrating ingredients. Hazan’s favorite: Nigelle DS Treatment for Tender Feel ($26; sleekhair.com)

3. Gloss over it
Getting a clear gloss treatment at the salon (typically around $50) gives colored strands an extra layer of protection from the sun, says Hazan. (The effect lasts about four to six weeks.) You can gloss at home too with Fekkai Glaze ($28; sephora.com).

4. Cleanse with a neutralizing shampoo
If your color has already taken on an orange-y tint, Hazan says to neutralize it with a purple-toned shampoo such as Clairol Shimmer Lights ($10; haircareusa.com). But don’t suds up with this formula more than once a week; too frequent cleansing can leave your hair looking ashy.