As this can be a Swyama Siddha Hanuman Mantra it doesn't have being chanted for a hard and fast number of Mantra Repetitions for being able to use it. Distinctive worship and rituals and principles pertaining to direction, sitting mat, and counting rosary will not be advisable for chanting this https://www.youtube.com/watch?v=ufkmD95y7fE&t=32s