When opening a serum vial, it is important to first clean the area around the vial with an alcohol swab. Next, locate the small rubber stopper on top of the vial. Using a clean needle, puncture through the center of the rubber stopper. Be sure not to touch the sides of the stopper or needle as this can contaminate the contents of the vial. Finally, attach your needle and syringe to the vial and draw out the desired amount of serum.