STRAIGHT HAIR

THE shape of your follicles (the tiny pores on the scalp that hair grows out of) governs curliness. Straight hair means perfectly circular follicles. The more oval-shaped the follicle, the curlier your hair.

Straight hair is generally thick, resistant to damage and shiny. The sub-groups are: A: Very fine and wispy. B: Medium thickness C: Thick and coarse

HOW TO CUT IT: Try a strong fringe or add layers for shape. Type A hair can look flat, so it needs layers. Too many, and it may look wispy. A side parting gives volume. If worn short, cut every five weeks. Types B and C can wait six to eight weeks. Type Bs can get away with almost any cut, but Type C can be hard to manage; you’ll need layers to break it up.

HOW TO STYLE IT: Straight hair benefits from extra volume. Do this is by flipping your hair upside down and blow-drying at the roots. It also tends to get greasy.

For Type A hair, it’s vital you find a shampoo and conditioner that leave it soft without weighing it down (Louise Galvin Sacred Locks Shampoo and Conditioner for Fine Hair, from £22, louisegalvin.com or Kerastase Aura Botanica Shampoo and Conditioner, from £15.90, feelunique.com).

Don’t expose Type A to excessive heat; it can suffer damage. Many curling tongs run at 220 degrees — look for a set you can turn to a lower temperature. Products designed to make hair look shiny will just weigh yours down.

Type B is perfect for styling as it’s shiny, with volume. It looks lovely hanging loose or in a ponytail. You can curl straight hair, with varying degrees of success — Type C won’t hold curl well.