to form CSR

Dear Sirs,


Plz suggest HOW TO PLAN expenditure for incurring CSR i.e [Corporate Social Responsibility] activity.

Ours clients are 7 group companies including 2 listed and 2 foreign companies & are planing to carrying expenditure on CSR[Corporate Social Responsibility]. Plz Suggest whether to form a Co-operative ,seperate trust and contribute to corpus fund or to form a Sec 25 Compny or any other ? to get the beneficts of the provisons under various respective Acts i.e. Income tax act,companies act , indian trust act or cooperatives society act.
 
Awaiting Expert Comments on the issue.