There is not any rule for chanting this mantra however it is made use of at distinct sites as per the specific situation. For anyone who is working with it then utilize it while in the fashion specified under.  ॥ ॐ नमो भगवते रुक्मिणीवल्लभाये स्वाहा ॥ This might aid to affect https://www.youtube.com/watch?v=WG3Cevb_VHM