How it works

1. Start almost dry

   Hair 80 to 95 percent dry: nearly dry to the touch, with a little cool left in it. This is the rule that decides everything. Too wet and the curls won't set by morning; bone dry and they won't hold. Wash in the evening and let it air dry, or blow dry on cool until it's almost there.

2. Place the rod

   Clip the top section at the crown so the curls start high, not flat. Lay the rod across the top of your head like a headband, the two ends falling in front of your shoulders.

3. Wrap

   Take one side, twist it gently away from your face, and wrap it around the rod from the crown down to the ends. Secure with a scrunchie. Repeat on the other side. Let the clipped crown section down and wrap it in with the last turns; the clip comes out.

4. Sleep

   The bonnet goes over the rod and your hair. Back, side, front: sleep how you sleep.

5. Unwrap

   Slide the scrunchies off, unwind each side, and slide the rod out. Shake the curls loose with your fingers. Don't brush them; brushing turns curls into waves.

What to expect

1. Night one

   Practice. The wrap feels odd in your hands and the two sides may not match. That's normal, and it's why the card is in the box.

2. Night two

   Your hands know the way. About five minutes, start to bonnet.

3. After that

   A habit, like brushing your teeth. Wash in the evening, let it almost dry, wrap, sleep.

By hair type

• Fine hair

  Go a little drier, around 95 percent, and wrap tighter. The grip strip on the rod is being tested for exactly this.

• Thick hair

  Split each side into two sections and wrap both around the same rod. Give it the full night.

• Wavy or curly hair

  Smooth each section with your hands before wrapping. The rod gives shape when the hair starts almost dry.

• Shoulder-length hair

  The Long rod works from the shoulders down. A shorter rod is in testing for shoulder-length and shorter hair.

• Side sleepers

  Wrap a little higher so the rod sits above your ear. The bonnet is designed to keep it there.

If the morning isn't what you hoped

Six things that go wrong with any curl set, what usually causes them, and what to change tonight.

• Nothing happened.

  Usually: the hair was too wet, so it never set, or bone dry, so it never took the shape.

  Tonight: Aim for 80 to 95 percent dry: nearly dry to the touch, with a little cool left in it.

• The curls dropped by lunch.

  Usually: a loose wrap, or brushing them out in the morning.

  Tonight: Wrap tighter and closer to the rod, start a touch drier, and shake the curls out with your fingers. If you use a hold spray, a light mist before wrapping, not after.

• The rod slipped in the night.

  Usually: the rod sat too low, or the bonnet went on loose.

  Tonight: Lay the rod higher, above the ears, and pull the bonnet snug over everything. Side sleepers: higher still.

• Flat at the crown.

  Usually: the top section was never clipped up, or wrapped last and loose.

  Tonight: Clip the crown up first, wrap the sides, then let the crown down and wrap it in with the last turns.

• One side curled, the other didn't.

  Usually: uneven sections, or one side twisted the other way.

  Tonight: Part down the middle, the same amount of hair on each side, both sides twisted away from the face, the same number of turns.

• Frizz, or a dent at the ends.

  Usually: rough hair before wrapping, or a thin tight tie at the ends.

  Tonight: Smooth each section with your hands first, and use the wide scrunchies from the box, not a thin elastic.