Good advice from everyone, and lots of reading available on the internet with some google searches. I just got started with SW a few years ago myself, and learned a few things the hard way. So here is my tip for you.
Set up a quarantine tank right from the start. It can be simple to keep running. Just use an old canister filter, and change water using the old water from your display tank after a water change. Keep the tank bare with maybe a bit of live rock. When you get new fish, QT them for a min of 2 months using the hyposalinity method. Here is a good write-up for that.
http://www.reefsanctuary.com/forums/...t-process.html
You can indeed start off without a QT, but after a year or less, and a couple of episodes of Marine Ich, you will very much regret that decision, I'm sure. Marine Ich is very different from FW Ich, so don't get complacent if you previously dealt with it easily with FW. That will not be the case with SW.
Good luck, and look forward to seeing your progress.