First thing will be a CUC (clean up crew) Consisting mostly of snails, hermit crabs (for some), shrimp if you like but with your size tank you'll probably get bigger fish who may eat the shrimp-lol.
But of course you'll only want to do this once the tank is cycled
Research your desired fish carefully. You'll be wanting Reef Safe only. Make a list and then build your tank around their specific needs.