How to Diffuse Curly Hair Without the Frizz

Air drying is gentle, free and slow. For many curls it is also flattening: hair that spends four hours wet spends four hours being pulled straight by the weight of the water. A diffuser dries curls in the shape you want them to keep, with lift at the root that air drying rarely gives.

It is also the step where a good wash day most often goes wrong. Too much heat, too much air and too much handling will turn defined curls into a cloud. The method below is designed to avoid all three.

What a diffuser does

A hair dryer's nozzle concentrates air into a jet, which is exactly what blows curl clumps apart. A diffuser spreads the same air over a wide bowl, so it dries the hair without moving it.

Before you start

Your hair should be styled and still wet, with your leave-in and gel or mousse already applied, as set out in The Wash Day Routine. Scrunch out the dripping excess with a microfiber towel first. If your stylers do not include heat protection, apply a heat protectant now.

Set the dryer to low or medium heat and low speed. High heat dries the outside of the curl before the inside and damages the cuticle. High speed is frizz, mechanically applied.

The method

1. Hover

Hold the diffuser a few inches away from your hair and move it slowly around your head, without touching the curls. Do this for three to five minutes. The purpose is to set the cast: the thin shell of gel or mousse that holds each curl in shape. Once the surface is set, the curls are far harder to disturb.

2. Cup

Tilt your head to one side. Gather a section of curls into the bowl of the diffuser from underneath and lift it toward your scalp, so the curls sit coiled inside. Hold for twenty to thirty seconds. Lower the diffuser, move to the next section and repeat.

Turning the dryer off while you move between sections is slower, and it gives noticeably less frizz.

3. Lift the roots

Tip your head forward and to each side as you work, so the roots dry away from the scalp. For more volume, slide the prongs of the diffuser in at the root and hold them there.

4. Stop early

Dry to about eighty or ninety percent, then leave the rest to the air. Hair diffused to bone dry tends to be frizzier and less elastic.

5. Break the cast

When your hair is completely dry, and not before, scrunch upward with clean hands to soften the cast. A drop of light oil on the palms helps.

The less you touch your hair while it dries, the better it will look when it is dry.

Common mistakes

• Raking fingers through wet curls mid-dry. Every touch separates a clump.
• Starting with the cupping. Without the hover step the cast has not formed, and lifting curls into the bowl disturbs them.
• Too little product. Diffusing needs hold. If your curls frizz however carefully you dry them, use more gel or mousse, on wetter hair.
• Rushing with heat. If you are short of time, plop first to shorten the job instead of turning the dial up.

Does the dryer matter?

Less than the technique. Any dryer with separate heat and speed controls and a cool setting will do. Where an expensive dryer earns its price is in consistency: it holds a steady, moderate temperature instead of drifting hotter.