Please don't do this. It is cruel and inhumane. You are taking away the ability for your rooster to do what he was made to do. You can't alter an animal just for your own wants or needs.
If you can't keep your rooster, give him to someone who can provide a nice home for him.
Decrowing a rooster is very painful, and incredibly risky. Birds can die so quickly under anesthesia. Why put your rooster through that?
Please, reconsider whether you really want to do this. In the end, you have to decide what will be best for your rooster, and not what would be best for you.