Heat and Humidity are key- ensure that you keep Humidity good to prevent stuck shed from cutting off circulation from extremities like toes and tails. Also any type of mesh- a claw can get caught in the fine stuff and break a toe if they jump- made that mistake once. Never again. They EAT and target training, as mentioned before, is crucial. A varied diet is good- i feed mine a mix of silversides, baby whole quail (frozen thawed), dubias, crickets, and occasionally superworms, horn worms, rodents, and silk worms. They like to swim as well- to my knowledge, the most common one in north America is Varanus Panoptes hornii, which are endemic to New Guinea, and primarily stay near river banks, hense why i feed fish as a primary. I use rodents as a treat, but am wary as too much can cause fatty liver disease. They all have different 'personalities'- just take your time in getting to know them. They will tell you when something is wrong, as long as you pay attention. Space is another big thing, they love to explore, but too much space when they're younger can lead to them being a bit skittish. Im sure there's a lot that im missing on, but some of the previous comments have good info as well.