Stretch without heat by setting your hair while you sleep. Both methods below work on damp hair, never soaking wet.
Overnight braid-out
Section the hair, apply a light cream, and plait loosely. Six to eight braids give a soft, voluminous wave.
Bantu knots
Twist small sections around two fingers and coil into a knot. Fewer, larger knots give looser curls; more, smaller knots give a tighter spring.
Unwind in the morning
Take the set down with oiled fingertips and separate gently. Do not comb, just finger-fluff, or the definition disappears.