It is my sisters big day here in...?

It is my sisters big day here in Somalia, me and all the village people are going to stone her for the crime of speaking her mind and showing her ankle in public. First we strip her naked then we all stone her while chanting "Allah we praise you", I just hope she is really scared on the big day I mean we want a good show. So should I choose a merciful big stone or a harsh many medium stones.