It's in your best interest to go ahead and get more live rock, or at least base rock now. I got mine from oceanproaquatics.com the hawaiian base rock. If you don't get it all now, each time you add a new peice you'll start a mini cycle, ammonia spike, then nitrite spike, then extra nitrates. Saltwater creatures are very easily stress out and adding rock after rock will more than likely result in losses, costing you more money in the long run.
To cycle the tank propery, add in all your live/base rock, along with a dead shrimp from the grocery store. test your water every few days (or every day) for ammonia nitrite and nitrate. keep a log in a notebook or on your computer. once you see a spike in ammonia, a spike in a nitrite, then a spike in nitrate, and then 0 ammonia 0 nitrite your cycle is complete and you can add your first fish.
I would not worry about doing any cleaning at all untill your tank is completely cycled (after all your live rock is in)
you will NEED to go online and buy a HOB
(Hang on Back) Protein skimmer. I bought mine from reefwarehouse.com look into the reef octopus by coralvue.
I would also take the foam filter pads out of your filter and just use the pump for extra water flow and to run carbon later on if you need to. The live rock will act as your biological filtration where the bacteria will grow and complete the nitrogen cycle, and the Skimmer will be your mechanical filtration taking organic molecules out of the water (taking place of filter pads in a fresh water system)
(note that this is one opinion on an effective way to sustaining a saltwater aquarium. There are other options but this methed is generally accepted as the best way to go about it.)