When one of my Roos was about that age, he would flog me non stop. I started wearing long sleeves and leather work gloves in the yard and when he started to attack I reached down and pinned him to the ground until he was calm and then picked him up and carried him around under my arm facing backwards (to avoid biting) while I did my chores in the yard. I would also take a few moments and hold him down at hen level and talk crap to him and let the hens peck at him a little lol he got the message after about 3 times. Once u put him down he should walk away, if not repeat. He will eventually understand that you are in charge. He also calmed a lot once he got over the teenager stage haha