The best complete sentence is: Marta se levanta y después se viste.
After Marta gets up, she then proceeds to dress herself. "Después" indicates a sequence of events, clarifying that dressing comes after getting up.
This choice, "después," signifies a temporal sequence, indicating that the action of getting dressed follows the action of getting up. It establishes a clear order of events in Marta's morning routine, conveying that she first rises from bed and then proceeds to dress herself.