I was being a tad facetious and hoping that others would chime in.
Much of the sterile stuff is wrapped in blue wrappers so a good general rule is to stay away from blue areas. Watch how the nurses move around a sterile field and try to mimic them.
Ask a LOT of questions. There will be a lot to absorb. Take a little notebook and jot down your questions so you can ask them during quiet times: beginning and ending times of a big case are probably too busy but in between there should be calmer times where you can chat with the circulator.
Check out the "So you're observing in the OR" thread.
Look here and watch a few surgeries online:
http://www.or-live.com/
Talk to as many people on the OR staff as you possibly can: nurses,Docs, techs,housekeeping,booking people, PACU. Everyone has their own views on what's going on.
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