Say OM VAJRA BEGAMA AH KRAMA HUM mantra(a abstract mantra to purify holy objects that anyone can use) 108 times for the nadis system while you hold the pentacles in the hands in a madra formation, Left hand Thumb to right hand first finger with left hand palm down and right hand palm up at nipple hight of chest(in between them). The pentacles can be in thumb and finger if they can fit or you can do some at a time.
I can tell if a pectacle is working by feeling energy coming off it. I found out when I said a different mantra while charging some pentacles. It's "om zoom"(positive energizer also say 108 times for full effect). I felt(charging one at a time) more energy in the pentacle when saying it a few times in mind. Probably more if I say it.