J.B.
In my opinion he is way too little for any kind of discipline, he is a little bity baby:) I think every time he does it saying "ouch!" in a high pitched voice and putting him down immediately will help. I don't think you have to walk away or anything but put him down. Then if you pick him up and he goes for the hair, put him right back down. This should get his brain to realize that the action of grabbing your hair equals no fun for him. Maybe even say ouch as you are touching his hand to get it out of your hair, just to help with the correlation. That is what I did when my little guy started chomping on the breast. I said ouch and ended that feeding, to get the message that biting the breast equaled something he didn't like. Worked pretty well. I would definitely not let him pull your hair though, too painful!! Good luck!