Tattoo artist haram or Halal

I’m 18F and I’ve been practicing tattoos on fake skins. I’ve gone pretty good at it and was wondering If I could open a spot in LHR for tattoos and piercings. Question is that if it’s a halal thing or haram. I know there are non- muslims and people from various sects too that are allowed to get tats. Would it be haram for me to give tats to such people?