Instructions
Increase the size of your flock. Adding more hens and possibly another rooster can help subdue an overly aggressive rooster. By adding more individuals to the rooster's chicken society, you're giving him more opportunities to establish his own pecking order and reinforce it. This is sometimes enough to limit his aggressive behavior to members of his own species rather than trying to enforce a pecking order that includes you.
Establish that you are the top rooster. Many rooster owners see reduced aggression in roosters who are led to believe that their human caretaker is the top rooster in the coop. To employ this method, first invest in protective gloves and a sturdy shirt or coat. At the first sign of aggression toward you, grab the rooster and hold him. Regardless of how much he struggles, do not put him down until he becomes calm. If he struggles again when you bend down to release him, raise him back up and hold him again until you can release him docilely.
Get the rooster to submit to you. Use this method if the previous method doesn't seem to be working. At the first sign of aggression, pick the rooster up by his feet and hang him upside down. Hold him upside down until he stops flapping and becomes calm; then release him. This method can be dangerous because the rooster's lungs can collapse when held in this position. Be careful when hanging roosters upside down and be aware of the risks associated with it.
Establish that you are not a rooster. This method conflicts with the previous two methods, so choose one and stick with it rather than mixing and matching and confusing the rooster. Aggressive roosters probably assume that humans are a threat to their coop, which is why they attack you -- prove to the rooster that you are a caretaker, not a threat, and his aggression may decrease. Do this by bringing him some food every time you enter the coop. Never walk directly toward him as this can be interpreted as threatening.
How to Make Roosters Less Aggressive
Some roosters are naturally aggressive and some are not. This characteristic depends as much on individual differences as species differences, and often can be traced back to upbringing as well. Roosters are pre-programmed by nature to defend their hens against threats to the coop. If a rooster sees you as a threat, he will not hesitate to attack. If your rooster is aggressive toward humans, you can try a few different techniques to reduce his aggression level.