Calatheas follow their circadian rhythm, moving and opening their leaves towards the sun throughout the day. It’s particularly fun to watch calathea concinna’s chevron patterned leaves go through this daily transformation.
Calatheas prefer medium light; too much direct sun will make their markings fade. This plant likes to be kept evenly moist, never dry and never too wet. Put it on a tray of pebbles to keep the humidity high so that the leaf edges don’t turn brown or get to dry. Only replant when the roots and plant have grown quite large. This probably won’t be for a year or more after you bring the plant home. When you do decide it’s time to replant, do so in the spring.