Calathea Vittata does not like direct sunlight. Protect from the sun, place where it can receive medium light. Calathea Vittata need to be watered regularly and not allowed to dry out between waterings. Simply stick your fingers in the top two inches of soil and as you feel is starting to dry give your plant a drink. Try using filtered water. Use a humidifer or watered pebble tray to help your plant get some extra moisture.