1) They require plenty of sunlight. Ensure around six hours of sunlight each day.
2) Make sure you thoroughly water this plant so that the soil becomes well soaked.
However, make sure that you do not overwater as this can then lead to root rot. You should let the soil dry up completely before you water the cactus again.
3) Astrophytum requires well-draining soil that can get rid of the excess water in the pot. A coarse texture of the soil with mostly inorganic material and cactus soil is recommended.
4) Use a stable fertilizer that has a good balance of all nutrients. Make sure that you dilute this fertilizer with some water as it can cause root burn.
5) It is propagated by seeds or grafting of pups.