As this can be a Swyama Siddha Hanuman Mantra it doesn't have to be chanted for a set amount of Mantra Repetitions for being able to use it. Unique worship and rituals and principles pertaining to way, sitting down mat, and counting rosary usually are not advised for chanting this https://www.youtube.com/watch?v=ufkmD95y7fE&t=32s