Scalp and lengths are different jobs
Shampoo is for the scalp and conditioner is for the lengths. Work shampoo into the roots with your fingertips and let the suds rinse through the rest; piling hair on top of your head and scrubbing it only tangles and roughens it. Apply conditioner from the ears down, leave it for a minute or two, and rinse with cooler water.
By texture
- Straight and fine hair shows oil fastest, so it can be washed daily or every other day with a light conditioner kept off the roots.
- Wavy hair does well on two or three washes a week and lightweight products, because heavy creams pull the wave flat.
- Curly hair is drier, since scalp oil travels poorly down a spiral, so wash it once or twice a week with a gentle sulfate-free shampoo and condition generously.
- Coily hair is the most fragile and the driest, and it suits a wash every week or two, a deep conditioner, and a cream or oil afterward to seal in water.
Curly and coily hair should be detangled only when wet and full of conditioner, with fingers or a wide-tooth comb, starting at the ends and working up. Brushing curls dry breaks them and produces frizz. Blot with a cotton T-shirt or a microfiber towel rather than rubbing with terry cloth. A satin or silk pillowcase or bonnet cuts friction overnight. Braids and other protective styles should never hurt; constant tension along the hairline causes permanent loss.
Heat
Use a heat protectant every time, keep irons below about 350 degrees for fine hair and 400 for coarse hair, and never put a flat iron on damp hair, which boils the water inside the strand.
Scalp trouble and shedding
Dandruff is usually a reaction to a scalp yeast and not dryness, so oiling the scalp makes it worse. Use a shampoo containing zinc pyrithione, selenium sulfide or ketoconazole, leave it on for five minutes before rinsing, and see a dermatologist if a month brings no change. Losing fifty to a hundred hairs a day is normal. A widening part, a receding hairline or sudden patches are worth a doctor's visit early, since the treatments that exist work better at preserving hair than at regrowing it.
Tip Bring a photograph to the barber or stylist and say how many minutes you spend on your hair each morning, because a cut designed for a blow-dryer fails anyone who air-dries.
