All you have to do is to give your international coordinator the name of the company ,your job responsibility,your supervisor name  and the company e-verify number.And then your university will send you the new I20 with all this information and you need to send that packet to USCIS .I am in a 17months OPT extension working now .If you are not working then get this information from any consultancy and it will work.I have seen so many people getting extension without working.