Hello hrsandipan,
I think Hussain & Gaurav Sareen have raised valid points, that need careful & serious rethinking @ your end.
Coming to the current situation, one way to handle/correct such category of people is to create situations where they 'SEE' for themselves the damage/repercussions of their actions. No amount of 'telling/teaching/training' will help WITHOUT them ACTUALLY observing/seeing the consequences of their 'unthought' actions--since they are more prone to ignore other's advice, however well-meaning/well-intentioned.
In a nutshell, make them 'realize themselves' thru whatever teaching/training you wish to give. Without this aspect embedded into your whole effort, I don't think it will achieve the desired purpose.
All the Best.
Rgds,
TS