Once the marks are checked for accuracy your skin will be held very lightly in a pair of custom made clamps. DON'T PANIC. The clamps most people are used to, are called Duval Clamps. These are vicious, toothed clamps that are clicked down to cut off blood supply so that you feel less from the piercing. DO NOT USE DUVAL CLAMPS. The clamps most piercers now use are designed specifically for the job of piercing. They do not click down and cause NO SURROUNDING DAMAGE. The sensation from the clamps is like being held lightly between finger and thumb.
The piercing is made using an intravenous cannula, which is a very sharp needle surrounded by a plastic sleeve, similar to those used in hospitals for drips. The ones that most piercers now use are imported from Germany and have a specially designed cannula that reduces the nip that is usually felt. The piercing takes about 1/8th of a second.