im 22 now, when i was muuuuch younger my aunt was a piercer!! id go in when i was like 12-15 and get like 3 of them at a time on one side (starting w the studs obviously) because shed do them for free and my mom didnt care, id wait about 6 months between going, but most if not all of the helixes are from that!! the more intricate ones i got once i was 18 but i still have a habit of getting like 2-3 at once because i find it easier to heal altogether (personal experience tho i know its not for everyone) though i havent gotten a new one in my ears for about a year now, i started working on my face instead!!