Tell us about your setup... size of tank, pounds of LR ect.
Live rock will work IF it is uncured or has a adequate amount of die off. I would add a uncooked cocktail shrimp and let the tank run for a couple weeks. After the ammonia and nitrites have spiked and fallen back to 0 your cycle is over. At this point you should have around 20+ppm nitrates. Do a 20% water change and add your first fish along with some cleaners. From there... add another fish every few weeks if desired until you have all of the fish you want. Waiting longer between fish will not hurt anything but I wouldn't add more than one every few weeks.
the size of my tank is 60 gallons, about 30 pounds of liverock,excalibur protein skimmer,aqua clear 70 filter, and about 40 pounds of reef sand and some base rock and some artificial corals
Sounds like a good start!! You may want to consider another 20-50 lbs of base or live rock.
Are you doing a reef tank?? If so, what lighting do you have or plan on??
With the cycle, I'd do as suggested above. Be patient and try not to rush the tank.
HTH,