As it is a Swyama Siddha Hanuman Mantra it does not have being chanted for a hard and fast range of Mantra Repetitions for having the ability to use it. Special worship and rituals and rules pertaining to direction, sitting mat, and counting rosary aren't encouraged for chanting this Hanuman https://www.youtube.com/watch?v=ufkmD95y7fE&t=32s