You'll need to be a little more specific in your question.
I would say a tank at least 5 gallons per newt(a minimum of 10), water at least 4 or 5 inchs deep. Substrate should be large enough the newt cant accidently ingest any during feeding. Good filtration, but little water movement. There should be at least some land area with plenty of hides, both on the land and in the water. Temperature should be kept low, and cleaning easy.
Plants, while not nescasery, can help maintain water quality, looks pleasent and help maintain a healthy viv.