Slice is giving good info. I'll see if I can add
1.) Strongly reccomend getting your own RO/DI water purification unit. you can get them for as little as $100.00 for a decent one with low Gallons per day output. this is crucial for two reasons.
a.) you want to have pure water otherwise things that come in from tap water will slowly contaminate your tank and you may always have nasty things like cyano growing in there, not fun.
b.) its nice to have your own filtration so you can make water when you need it, don't have to go to the store to get it, initial cost is higher, but overall very cost effective in the long run. Especially handy to have in emergencies when you may have to do a good sized water change becuase of equipment failure or something you may have done wrong.
2.) Be sure to get your live rock that you need for the tank prior to beginning your cycle.
you should have between 1 - 1.5 Lb's of LR (live rock) per gallon of tank water. So in your case about 75 lbs. the live rock is very porus and therfore has alot of surface area for the bacteria to grow on which will help to complete your cycle. if you add rocks later they may cause ammonia spikes which will start a mini cycle and be very hard on your livestock.
3.)Strongly suggest a protien skimmer for the beginners. they process leftover foods and waste before it can breakdown and become ammonia.
4.) Get all your own test kits (this should have been #1) you will need test kits for ammonia, nitirtes, nitrates, high range PH at the very least.
5.) patience... this is probably the number one thing that seems to go wrong with most first timers. they eitehr don't know about the cycle at all or can't wait the month or so that it takes to fully complete. add livestock, livestock dies, they come back asking why thier nemo died. Just weait it out. as we've all been told several times.... Nothing in Saltwater happens fast.
6.) when you get all set up and would like advice on livestock lits, rock formations, filtration, ect ect do ask away
ohh and I've found out the hard way... no matter how good you think your tank looks, people are going to tell you " Pictures of it didn't happen"