To Make Curly Hair Straight:
On day one, prep damp hair with a pea-size drop of styling cream, such as PhytoSpecific Curl Legend Curl Sculpting Cream-Gel ($28, phyto.com). Blow hair dry in sections, working with a large, round natural-bristle brush, says Sharon Medina, an educator for the hair-care company Inoar. On day two, add a bit of oil, like ColorProof TruCurl Anti-Frizz Oil ($25, colorproof.com) to your hair to seal the cuticle, then restyle with the dryer. On day three, simply use a flat iron. “It seals the cuticle and boosts shine,” Medina says.
To Make Straight Hair Curly:
Distribute an oil-, gel-, or cream-based product through damp hair, then fashion sections into pin curls (for tighter curls, wrap hair around one finger, then secure with a clip; for looser…