Jennifer Morrison's fashion-forward take on a mohawk is a really cool way to wear an updo if you can't stand fussy chignons or girly braids. Start with a section of hair right at the front, and split it into two sections. Twist these sections round each other, and then incorporate a bit more hair into either side before doing the next twist, and pin at either side to keep the hair sitting flat around the twist.
Repeat all the way down the back of the head, adding hair as you go and continuing to pin down, like you're doing a two-strand twisted version of a french braid. The ends can then be twisted or plaited and folded under at the nape of the neck and secured with bobby pins. Once the twist is secure, pull gently on each section to fluff it up.