Do so much research, till you can't possibly do anymore and you feel like you know it ALL! lol
To take VERY good and proper care of them, is a HUGE commitment! You can't be a slacker and keep Discus well. Do research on where you get your stock, also there is a thread somewhere about how to spot a GOOD healthy Discus, try and find it!
Good and happy fish keeping to you. There are also threads about kinds of plants which do well in the warmer water. Good to know too.
New to FW fish? First tank in a long time or EVER??? Need some info on keeping fish?
Start here - Aquarium Advice Article
FW Favorites right now Clown Loaches, any shrimp - SW Vase Red Mangroves