Fill the tank up, add the fish, and monitor the water. All the fish you have are pretty hardy fish. But, make sure the water is at 86 degrees to prevent ich.
Add the sand and the 10gal of water that you saved and top the tank off with clean water. add the fish and monitor the water. How big is the tank? And what filter/filters are you running?
What kind of sand is it? If you have bought the right kind a sand it should take a couple days to clear up completely. Also what are your plans on a future tank, as for some of those fish can get around 2 feet.
Thinking about somewhere between 75 and 150 gal. Do you think that will be big enough? (sorry if I sound like a smart a**, but I really don't know the answer)