To safely use a flat iron on fine hair, use a steam-producing iron, such as Teflon-coated hot tool brands, and apply a heat protectant to hair before straightening. Use a lower heat setting and run the flat iron through the hair consistently, not stopping at any one section longer than another, and quickly. Only use a heated tool once or twice a week.
Do not style hair with a flat iron while it is still wet to avoid steam damage. Wet hair produces a boiling effect that boils the center of a hair shaft. This causes a break in the walls of the medulla and produces bubbles in the shaft that decreases shine. Hair becomes rough, dry and is more easily snapped off when it is styled while wet.
Using a flat iron daily causes frizzy hair of differing lengths because of hair breakage. Change the flat iron periodically when there is buildup on the plates or the surface of the plate becomes sticky. This buildup and stickiness is caused by burned hair cells and it causes more damage to hair if used for too long. The signs of heat damage include dull, dry hair that breaks easily, as well as damage to the scalp or hair follicle and reduced shine. If these are happening to one's hair, seek a professionals help to rehabilitate the strands.