try doing a bunch of quick practice sketches of heads and hair, in different styles and blowing in different directions. sketches allow you to relax more and not overthink the placement of every strand of hair. if you overthink and draw hair too slowly, it might come out in a way that looks to stiff and controlled.
sometimes you have to draw a strand or section of hair that's flying in a different direction than the rest of the hair, or sticking out from the head more. if you do that right, the hair looks less stiff.
another thing you might want to try with some hairstyles is having some bigger/thicker sections of hair, together with some thin pieces of hair that float upward more.
always consider the weight of the hair, (long hair being more weighty than short hair) and also how loosely or stiff/tight it is styled. (that affects how much the wind/gravity affects it)
one last tip: be careful not to unnaturally curve the hair. (if it's straight) this is hard to get right -__- but try not to curve it too much or in the wrong place because then it just looks forced and bent instead of a gentle curve. although sometimes, hair curves are exaggerated for artistic effect... (actually, so are weights of hair. sometimes long hair is drawn as if it's really lightweight)