If we keep our mind on Christ, we cann't help but be a witness. We were born again to be a witness. It helps to get the salvation scriptures written out on paper. That way you share the word that will not return void. The reason it is easier to share online is because it ain't so personal.
But I tell ya, when you see that eternal light go on in someones eyes, and know that their eternal destiny has changed, you will most assuredly get addicted to the proclamation of the Gospel of Jesus Christ. Fear will always come against you. But recognize it as your spiritual enemy. Submit yourself to God in obediance to the great commission, and tell that spirit of fear to go!!!! By the perfect love of our Lord Jesus Christ.
Quit allowing your short commings to over ride the enabling power of God. For God does not call the equipped, but equips the called. The fields are white, all I can say is get you some of it!!!!!!