This article is from the Piercing FAQ, by Anne Greenblatt with numerous contributions by others.
Get plenty of rest the night before. Eat a good meal and drink plenty
of fluids within 6 hours of getting pierced.
Do not consume alcohol, large amounts of caffeinated beverages, or
blood-thinning medications within 12 hours prior to or 24 hours after
getting pierced (or 24 hours after the piercing stops bleeding). If
you must take blood-thinning medication discuss this with your piercer
and your doctor prior to your appointment.
Wear clean clothes. Depending on the location of your piercing, do not
wear restrictive clothing.
If you are getting a facial piercing, do not wear makeup around the
piercing site. If you are getting an ear piercing, wear your hair away
from your ear.
If you are considering getting more than one piercing in a single
session, consider factors such as your body's ability to heal multiple
piercings and comfort during the healing period.
 
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