First you wait in a room full of patients and supporters. When your name is called you take a key and enter the changing room. You slip into a super large robe worn backwards, making you look as though you're about to graduate as a Doctor of Whatever, minus the festive hat. Then you wait in an anteroom until they call your name. The cheery technicians lead you to the table and get you situated. This takes about 5 minutes because it has to be very precise. Yesterday, Glenn Gould was playing the Goldberg Variations. Last week, it was various jazz singers, mixed in with Avril Lavigne and Aerosmith.
They slip my right arm out of my robe. I place my arms over my head in supports that make me feel somewhat less uncomfortable. They place a 1 cm bolus (a piece of fabric that targets the rays even more) over my right breast and tell me to stay as still as possible. I usually try to meditate. I never think about being zapped by radiation.
When it's over, I put my robe back on, go to the changing room and get dressed. I leave the clinic aglow with the probability that my tumor is melting away.