You are able to do this Shabar mantra chanting for eleven, 21, 31, or 41 times, the place and time of mantra chanting should be a similar for the volume of days you would like to do sadhana. You may use Rudraksha or Tulsi rosary to chant the mantra. https://edgaruoibu.smblogsites.com/32357977/5-essential-elements-for-most-powerful-sarv-karya-sidh-shabar-mantra-karya-siddhi-shabar-mantra-most-powerful-shabar-mantra