As that is a Swyama Siddha Hanuman Mantra it does not have being chanted for a set number of Mantra Repetitions for being able to utilize it. Specific worship and rituals and procedures relating to way, sitting mat, and counting rosary are not advisable for chanting this Hanuman Mantra. The https://www.youtube.com/watch?v=ufkmD95y7fE&t=32s