To cycle your tank, make sure once you get your rocks, rinse them well, I will say try to put it under the faucet and wash off any debri.
Then place it in your tank as you like and then let the tank sit for up to 3 weeks. make sure off course that you have all the equipment running as if the tank was already cycled. Some people may add live stock just to get some amonia and such to build up to help the cycle. I started with two damsels, One died after getting injured in my rock work and then second one is still in my tank after a year. You don't have to use fish to cycle you can just let the rock work do th ework, specially since it came with some die off. You need that believe it or not for the bacteria to build. I chose a sandbed for mine because I like the look.
Make sure you test the water constantly during the cycle so you can see how things fluctuate.