Ooooo that looks like a nice choice of substrate! Very natural looking.
The first thing I would do would be to leak test it! Place the tank on an even, level surface where nothing can be damaged by 5 gallons of water, and let it sit overnight. Come back in the morning, and check for leaks. If it leaked, take it back and exchange it. If it didnt, go ahead and put the tank in your desired location, go rinse the gravel outside or in the sink, place the gravel in the aquarium, you can make little hills and mounds to look more natural. Fill the tank, hook up the filter and the heater, then cycle the tank. I am not all that great with providing info on cycling, so I’ll let someone else explain That!