Congratulations, Jeanette. I'm pretty confident that you'll enjoy your Hassy greatly. It's perhaps the most thoughtfully designed MF system out there. (Translation: the system can be a money-pit of temptation )
The camera is really pretty simple, and if you think about things, most everything will be obvious. But, a Hassy book may help you get started more quickly. The Hasselblad Manual by Ernst Wildi (Focal Press) is a good one, but way thicker than it needs to be.
One significant caveat: don't touch the shutter release while you are advancing the film. There is a mechanical linkage between the lens, the body, and the film magazine (you'll see a little cam at the bottom of the lens when it's removed). All three need to be kept in sync, and partially depressing the shutter release when winding the film will cause problems. There is, however, a tool (available at Calument, B&H etc.) that can be used to fix the out-of-sync problem. $10 or so, and an essential investment.
Next stop - an extra film magazine or six, and then there are all those yummy Zeiss lenses.