There are some videos on how to take vital signs on one or two of the medical school physical assessment websites listed on this sticky thread:
The Virtual Blood Pressure Cuff -
http://medicine.osu.edu/exam/ - from Ohio State University College of Medicine. You can practice taking blood pressures online. To access the blood pressure cuff, scroll down to "Objective IV" and click the link that says "Take a blood pressure". When the player comes up follow the directions. You can re-cycle the player over and over to hear and input blood pressure readings that it quizzes you on.
The following members say Thank You: