As this is the Swyama Siddha Hanuman Mantra it doesn't have to generally be chanted for a hard and fast amount of Mantra Repetitions for with the ability to use it. Particular worship and rituals and rules pertaining to way, sitting mat, and counting rosary aren't encouraged for chanting this https://www.youtube.com/watch?v=ufkmD95y7fE&t=32s