To flat iron your hair, you should make sure that your hair
isn't wet, unless you have a flat iron that says it straightens wet
hair. Just turn on the iron and straighten somewhat small sections
of hair, one at a time. To do this you open the iron and start at
the top of the section. You glide the iron, and glide it down your
hair. Repeat as necessary. If you want, you can use some hair
protection products that protect your hair from the heat of the
flat iron, but that is your call.