Go reread the story of Moses and the burning bush.
In a nutshell God called Moses to return to Egypt and free the Jews and Moses refused and made a million excuses, such as stuttering. God allowed Aaron to be Moses' mouthpiece, but eventually Moses fell into place as a leader.
I've always been pretty shy myself. As a teen i was involved in youth groups a lot, and even in leadership positions as an older teen. From time to time i was expected to speak in front of the group. Even speaking in front of 10 people i knew terrified me.
I also was in a band during these times. I was more comfortable being in front of people that way and managed to speak to 200 people from stage when i was with the band. But solo i could barely talk in front of 10.
Also, as a teen i was involved in a group that did street witnessing in crack town. Mostly i listened, but from time to time i did speak. Usually people were impressed by what i said. But i wasn't always trying to speak. I spoke when i felt i had something specific to say, not just always talking. Perhaps there's a message for you there as well.
Personally i'm a bigger fan of 'sniping' than 'machine gun' conversations. I'd rather deal one on one with someone then send out a ton of words and hope it randomly hits someone.
It's just a combination of making yourself step outside your comfort zone and finding something that makes you more at ease. Or thinking of a different format to communicate.
I'm not trying to convince you that your goal is wrong, it may very well be what God intends, i'm just giving you different ideas and viewpoints to consider. It may be good to pray more for guidance than boldness.
I've also discovered that many people with that zeal envision some grand ministry, but they never end up going down that road. I think it's more of a human mindset to think that to be most effective means we have to be the most heard. But it's not every Christians role to be in the public eye to effect change.
It makes me think of an old Twilight Zone episode. This professor at a boys college, teaching literature and poetry, was being forced into retirement. He felt his life had been wasted and his only joy, teaching, had been taken from him. He was so despondent that he had no great accomplishments or impact on the world, he was ready to kill himself.
Then he walks into his classroom and it's filled with students. These are the souls of past students. One by one they tell him how he inspired them and the great things They accomplished, but wouldn't have without him. So while he never did anything himself, he raised up all sorts of heroes by his teaching and example, so he was regarded as being part of every one.
The point? We all want to be the big preacher in the spotlight, but perhaps your role is to disciple someone else who will be that person.
There are so many ways a person can go inside God's ministry, so make sure to seek the one He wants you to take, not the one that seems most obvious to your flesh.
