How to Curl Straight Hair So It *Actually* Holds All Day

When it comes to rocking curls all day, it starts with a strong wash routine. “Fine hair lacks the necessary strength to hold a curl, so consider a protein treatment to help add structure and strength. It’ll reinforce hair bonds, making the strands more resilient to styling—while rebuilding hair from the inside out and strengthening weak spots that typically cause curls to fall flat,” shares Everett. 

On the styling front, the experts recommend applying a lightweight mousse or volumizing spray to damp strands before rough-drying with a paddle or round brush. “Straight or fine hair tends to be smooth and lacks natural texture or grip. Adding a volumizing product creates the foundation that helps curls hold their shape. It gives them structure and a light hold from the start,” shares Ocando.

If you’re styling straight and/or fine hair, the experts want you to steer clear of heavy products that can weigh down your strands and cause your curls to drop before the end of the day. “When working with fine hair, use spritzes and sprays rather than creams or oils. These products are applied in a mist or lightweight gel-hybrid cream that gives enough grit, hydration and hold,” explains Patterson. 

Patterson recommends blow-drying over air-drying to ensure your future curls last longer and form its shape. “When we let the hair air dry, or work on already dried smooth hair, the hair bonds have already locked into place. Once they’re formed, you need heat, water or chemicals to break them again to take a new shape,” he shares. “When you work with straight hair that’s damp, use a primer (like Eva NYC) along with your round brush attachment. Then allow hair to cool before curling it. Your curls will be better suited to last!”

Once you finish styling and drying your hair, Potempa suggests using a smaller barrel curling iron—about 1 or 1.25 inch—even if you’re looking for looser waves. “A smaller barrel creates tighter curls that naturally relax into waves throughout the day. Fine or straight hair falls flat quickly, so starting tighter ensures your style holds its shape longer, even as it loosens,” she explains. 

Setting your hair is the most effective way to maintain your curls. As Prentice explains, “Think of it like the heat tells the hair where to go, and cold air, or setting it with duckbill clips or rollers say ‘stay there!’ Setting the hair creates volume and holds for the longevity of the look.” 

If you’re looking for a heatless alternative, Ocando recommends creating multiple braids throughout for a wavy finish. “This method is helpful for straight hair that doesn't respond well to curling irons, or anyone seeking a gentler, no-heat option that still adds body and movement,” she says. Start braiding damp hair (Ocando prefers French for more curl closer to the root) and apply a sea salt spray for texture and definition. Whether you prefer to air-dry or diffuse, your hair should be completely dry before you start unraveling each braid. 

According to Potempa, a flexible hairspray is a must for setting curls. While they’re cooling down, make sure to spray a generous amount in order to give you a soft hold. “If you want your curls to last, sealing them with the right hairspray is key. It can lock in shape while helping to resist humidity and frizz,” she adds.

Additional Experts

• Gregory Patterson is a celebrity hairstylist and a DIY Color & Styling expert for Sally Beauty. He’s based in New York City and has previously worked as a lead stylist for Project Runway. His previous clients include Britney Spears, Anne Hathaway and Julianne Moore.
• Cortney Prentice is the owner of Blush Avenue Studio in Sola Salons. With over 20+ years of experience, she specializes in bridal hair and makeup and cut/color services and has since expanded her services, now leading a team of 16 artists.