Hi Farouk,
As far as guys using an earring as a way to "witness", in my own opinion it does not seem to be anything others would really ask about as, so many unbelievers have them too, it is the "in" thing. Perhaps if one who is already a Christian and gets one, some at his work place or wherever, might ask him about it and it could be used as an opening. Yet, would not those he works with already know he is a Christian, without ear piercing? I'm fine with it. I have 3 in one ear and 2 in the other. Have not worn earrings in years but...when I got them, it was only to be "like the world", so, no witness there. I just rather have the Holy Spirit open opportunities for me to speak of Him to others. Not to say you are wrong and I am right...JMHO! :)
And my friend, that is all I have to say on this, okay? :)
God be with you!