I've seen a few posts around here about piercings in the last few days— questions about healing and the like. I'm not a piercer, just someone with a whole lot of piercings. When in doubt, call a shop and ask!
The basics: don't get anything pierced with the gun. Seriously, not even ears. Many studios will do lobes on anyone old enough to ask, and this is preferable. You cannot fully disinfect a gun, and Claire's staff don't usually have CPR or standard first aid.
The piercer: Your piercer should have a current standard first aid or higher, as well as CPR and some sort of infection control training. They should have completed an apprenticeship and ideally a course such the fakir musafar intensive. They should also be APP members, and participate in their ongoing training. They should be able to answer all your questions, no matter how basic. If you don't feel listened to, leave.
The shop: The shop should be spotless. Seriously. A good studio will be as clean as your dentists office if not cleaner. Tools should be single use or bagged from the autoclave, and unpacked in front of you. Piercer should change their gloves multiple times when setting up, and again to pierce you. Touch a surface, change your gloves. Used tools should go in biohazard containers to be sterilized or disposed of.
The jewelry: the jewelry used should be made of implant grade material, or it will reject. Neometal, industrial strength and anatometal are the only three jewelry companies who make jewelry that should go in a new piercing— ask for it, anything else is mystery metal crap.
The procedure: you'll be asked to come with something in your stomach if you book an appointment, or asked when you last ate if you do a walk in. You'll be asked to show ID and fill in paperwork about your health, you'll also sign a release hold harmless. If you're not feeling well, don't get pierced. If you're drunk or high, don't get pierced. If you're pregnant or less than 3 months post partum or nursing, don't get pierced.You'll then meet your piercer and discuss what you're getting done, and choose jewelry that suits you and the piercing you're getting done. Next you'll be given a lesson on aftercare, listen damnit. Follow your piercers instructions, don't google. The piercer will then clean the skin and mark you up with pen and check in the mirror to make sure you love the placement. Finally, after unbagging tools like a receiving tube or a clamp depending on the piercing, the piercer will unbag the sterile single use needle in front of you and get you to close your eyes and pierce you on an exhale. Jewelry will be placed immediately after. The piercer will wipe the piercing with an antiseptic again, and go over aftercare again, and give you a sheet with the information on it.
The aftercare: follow your piercers instructions goddamnit. Don't touch it except to clean it. Drink lots of water and get enough sleep. If it feels funny, go see your piercer ASAP. If it's red and hot, swollen or productive, go to the doctor and call your piercer.
Your mileage may vary, always always always defer to your piercer.