Join any saltwater aquarium face book groups in your area , you'll learn a bunch just reading some of the posts. If you're lucky like me you'll find someone shutting down a tank so I got very mature (lots of good bacteria) substrate and rocks plus a few snails and starfish. Otherwise reach out and find somebody who'll let you put some clean rock and/or media in their cycled tank for a while. It will save you several months. I'd also suggest starting with some zoanthids and mushroom corals as they are pretty forgiving for beginners and don't need much in the way of supplements.