They should never be dry. It needs to be sitting in water constantly, at least two or three centimetres during summer.
During winter the water tray can dry out before topping it up again.
They are best grown outdoors in full sun (minimum 6 hours). These guys love sun and will do best outdoors.
I find they do much better with a winter dormancy period. Canberra winters are ideal for them. Don’t be frightened of the frosts at all. Mine have been frozen solid. As long as the temperature rises above freezing during the day, they will be just fine.
Each trap will only close around 3 to 7 times before dying. If the traps are triggered without getting the reward of a meal, the plant will quickly die. If you want to feed it, the “meal” must be alive. The traps have tiny trigger hairs that require stimulation for the digestive action to occur.
My media for VFTs is a 50/50 peat moss & perlite mix.
Make sure the media is quite wet before potting up the plants.