I wanted one soooo long.. and now, finally, I don't know when to wear it except from photoshoots. :D
Measure how long you want your hairband to be. Just try in front of the mirror.
Cut out the piece from an old belt. Mine had 2 rows of spikes, I decided that one row will be enough to carry on my head..
Punch holes at the ends.
Put through an elastic string, make knots and you're done :)